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Functions — Free Maths AA SL Practice Questions

1FoundationSAQ-SReal-world applications of functions (e.g. growth models)s7 marksPaper 1~11 min
A small business purchases a delivery van for 2800028\,000 dollars. The value of the van depreciates linearly each year. After 55 years, the van is valued at 1300013\,000 dollars.
(a)
Calculate the annual depreciation of the van in dollars per year. [2 marks]
(b)
Find the value of the van after 88 years. [2 marks]
(c)
The business plans to sell the van when its value first reaches 10001\,000 dollars. Determine the year in which this occurs and evaluate whether the linear model is appropriate for this prediction. [3 marks]
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2MasterySAQ-SReal-world applications of functions (e.g. growth models)s5 marksPaper 1~8 min
The population of a small town is modelled by P(t)=50000+1200tP(t) = 50\,000 + 1200t, where PP is the population and tt is the number of years after 1 January 2020.
(a)
Show that P(t+1)P(t)=1200P(t+1) - P(t) = 1200 for all values of tt[2 marks]
(b)
Find the value of tt for which the population first exceeds 6500065\,000[2 marks]
(c)
A government grant is available only towns whose population remains below 8000080\,000 throughout the entire period 0t200 \leq t \leq 20. Determine, with justification, whether this town is eligible for the grant. [1 mark]
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3ChallengeSAQ-LReal-world applications of functions (e.g. growth models)s8 marksPaper 1~12 min
A company produces solar panels. The total revenue RR (in thousands of dollars) from selling xx thousand panels is given by R(x)=120x3x2R(x) = 120x - 3x^2, for 0x400 \leq x \leq 40. The total cost CC (in thousands of dollars) is given by C(x)=20x+400C(x) = 20x + 400.
(a)
Show that the profit function is P(x)=3x2+100x400P(x) = -3x^2 + 100x - 400[2 marks]
(b)
Calculate the value of xx that maximises P(x)P(x), and the corresponding maximum profit. [3 marks]
(c)
For x>40x > 40, the revenue function changes to R2(x)=80xx2R_2(x) = 80x - x^2, while C(x)C(x) remains the same. Evaluate whether the company can achieve a profit greater than the maximum found in part (b) for any x>40x > 40. Justify your answer. [3 marks]
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4FoundationSAQ-SReal-world applications of functions (e.g. growth models)s5 marksPaper 1~8 min
The height of a plant is recorded weekly. At week 11, the plant is 4cm4\,\text{cm} tall. At week 44, the plant is 13cm13\,\text{cm} tall. The growth is assumed to be linear.
(a)
Find the linear function H(w)=mw+cH(w) = mw + c that gives the height HH in cm after ww weeks. [3 marks]
(b)
A second plant grows according to G(w)=5w3G(w) = 5w - 3. Determine the week at which both plants are the same height, and state which plant is taller at week 1010[2 marks]
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5MasterySAQ-SReal-world applications of functions (e.g. growth models)s5 marksPaper 1~8 min
A biologist models the number of bacteria in a culture as N(t)=200×2ktN(t) = 200 \times 2^{kt}, where NN is the number of bacteria and tt is the time in hours after the start of the experiment. After 4 hours, there are 800 bacteria.
(a)
Show that k=12k = \dfrac{1}{2}[2 marks]
(b)
Write down the number of bacteria after 6 hours. [1 mark]
(c)
Determine the value of tt at which the number of bacteria first exceeds 50 000. Give your answer correct to the nearest minute. [2 marks]
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6FoundationSAQ-SDefinition and types of functions (one-to-one, onto etc.)s8 marksPaper 1~12 min
A function ff is defined by f(x)=2x+3x1f(x) = \dfrac{2x + 3}{x - 1}, for xR, x1x \in \mathbb{R},\ x \neq 1.
(a)
State the equation of the horizontal asymptote of ff[1 mark]
(b)
Show that f(a)=f(b)a=bf(a) = f(b) \Rightarrow a = b, and hence state whether ff is a one-to-one function. [3 marks]
(c)
Write down the range of ff[1 mark]
(d)
Find f1(x)f^{-1}(x), stating its domain. [3 marks]
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7MasterySAQ-SDefinition and types of functions (one-to-one, onto etc.)s5 marksPaper 1~8 min
A function gg is defined by g(x)=x24x+5g(x) = x^2 - 4x + 5, for x2x \geq 2, xRx \in \mathbb{R}.
(a)
Show that gg is strictly increasing on its domain, and hence that gg is a one-to-one function. [3 marks]
(b)
Hence find the range of gg[2 marks]
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8ChallengeSAQ-LDefinition and types of functions (one-to-one, onto etc.)s8 marksPaper 1~12 min
Consider the function f:R{1}Rf: \mathbb{R} \setminus \{1\} \to \mathbb{R} defined by f(x)=2x+3x1f(x) = \dfrac{2x + 3}{x - 1}. - A function f:ABf: A \to B is one-to-one if $f
(a)
= f
(b)
\Rightarrow a = bforallfor alla, b \in A$. - A function $f: A \to Bisontoifforeveryis onto if for everyy \in B$, there exists $x \in A$ such that $f(x) = y$. (a) Justify algebraically that $f$ is a one-to-one function. [4] (i) Show that the range of $fisis\mathbb{R} \setminus \{2\}$. [3]
(ii) Hence determine, with justification, whether $f$ is an onto function. [1 mark]
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9FoundationSAQ-SDefinition and types of functions (one-to-one, onto etc.)s5 marksPaper 1~8 min
Consider the function g:RRg: \mathbb{R} \to \mathbb{R} defined by g(x)=x34xg(x) = x^3 - 4x.
(a)
State what it means for a function f:ABf: A \to B to be onto (surjective). [1 mark]
(b)
Show that gg is onto. [2 marks]
(c)
The codomain of gg is now restricted to [0,+)[0, +\infty), giving h:D[0,+)h: D \to [0, +\infty) where h(x)=x34xh(x) = x^3 - 4x and DRD \subseteq \mathbb{R}. Find the smallest domain DD such that hh is onto [0,+)[0, +\infty)[2 marks]
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10MasterySAQ-SDefinition and types of functions (one-to-one, onto etc.)s5 marksPaper 1~8 min
The function hh is defined by h(x)=1x2+1h(x) = \dfrac{1}{x^2+1}, for xRx \in \mathbb{R}.
(a)
Show that hh is not a one-to-one function. [2 marks]
(b)
The domain of hh is restricted to x0x \geq 0. Show that hh is now one-to-one, and find an expression for h1(x)h^{-1}(x), stating its domain. [3 marks]
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11FoundationSAQ-STranslation, reflection, stretching, and compressions5 marksPaper 1~8 min
The function ff is defined by f(x)=x24x+3f(x) = x^2 - 4x + 3.
(a)
Write down the coordinates of the vertex of the graph of ff[1 mark]
(b)
The graph of ff is stretched vertically by a scale factor of 22 about the xx-axis. Write down the vertex form of the resulting function. [2 marks]
(c)
The graph from part (b) is then translated 11 unit to the right. Find the equation of the resulting function gg, giving your answer in the form g(x)=a(xh)2+kg(x) = a(x-h)^2 + k[2 marks]
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12MasterySAQ-STranslation, reflection, stretching, and compressions5 marksPaper 1~8 min
The function ff is defined by f(x)=x2+4x+5f(x) = x^2 + 4x + 5, for xRx \in \mathbb{R}.
(a)
The graph of ff is translated by the vector (32)\begin{pmatrix} 3 \\ -2 \end{pmatrix} to give the graph of a function gg. Show that g(x)=x22x1g(x) = x^2 - 2x - 1[2 marks]
(b)
The graph of gg is then reflected in the yy-axis to give the graph of a function hh. Find an expression for h(x)h(x) in the form h(x)=ax2+bx+ch(x) = ax^2 + bx + c[3 marks]
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13ChallengeSAQ-LTranslation, reflection, stretching, and compressions8 marksPaper 1~12 min
The function ff is defined by f(x)=x2f(x) = x^2, for xRx \in \mathbb{R}. The graph of ff undergoes the following transformations in sequence: 1. A horizontal stretch by scale factor 12\frac{1}{2} 2. A translation by the vector (13)\begin{pmatrix} 1 \\ -3 \end{pmatrix} 3. A reflection in the xx-axis Let gg be the resulting function.
(a)
Determine an expression for g(x)g(x) in the form a(xh)2+ka(x-h)^2 + k, where a,h,kRa, h, k \in \mathbb{R}[4 marks]
(b)
The graphs of gg and ff intersect at two points. Determine the xx-coordinates of these points and hence find the exact area of the region enclosed between the two graphs. [4 marks]
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14FoundationSAQ-STranslation, reflection, stretching, and compressions4 marksPaper 1~6 min
The graph of y=f(x)y = f(x) consists of two straight line segments: from (4,0)(-4,\,0) to (0,4)(0,\,4), and from (0,4)(0,\,4) to (4,0)(4,\,0). The function gg is obtained by translating ff by 22 units to the left and 11 unit down.
(a)
Write down the coordinates of the vertex of gg[1 mark]
(b)
Find the equation of the right-hand line segment of gg in the form y=mx+cy = mx + c[3 marks]
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15MasterySAQ-STranslation, reflection, stretching, and compressions5 marksPaper 1~8 min
The following shows the graph of y=f(x)y = f(x), where f(x)=x2+4x3f(x) = -x^2 + 4x - 3, for xRx \in \mathbb{R}. The graph of ff is reflected in the xx-axis to give the graph of gg.
(a)
Write down g(x)g(x)[1 mark]
(b)
Express g(x)g(x) in the form (xh)2+k(x - h)^2 + k, where h,kZh, k \in \mathbb{Z}[2 marks]
(c)
The graph of gg is then stretched horizontally by a scale factor of 22 about the yy-axis to give the graph of pp. Write down the coordinates of the vertex of pp[2 marks]
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16FoundationSAQ-SSine, cosine, and tangent functionss5 marksPaper 1~8 min
A water sprinkler rotates back and forth. The horizontal distance dd (in metres) from the sprinkler to the water jet's landing point is modelled by d(θ)=15sin(2θ)d(\theta) = 15\sin(2\theta) where θ\theta is the angle of the sprinkler head from the vertical, in radians.
(a)
Calculate the value of dd when θ=π6\theta = \dfrac{\pi}{6}[2 marks]
(b)
Find all values of θ\theta in the interval 0θπ20 \leq \theta \leq \dfrac{\pi}{2} for which d(θ)=7.5d(\theta) = 7.5[3 marks]
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17MasterySAQ-SSine, cosine, and tangent functionss7 marksPaper 1~11 min
The graph of y=acos(bx)+cy = a\cos(bx) + c for 0x2π0 \leq x \leq 2\pi has a maximum point at (0,5)(0,\, 5) and a minimum point at (π,1)(\pi,\, -1).
(a)
Show that a=3a = 3, b=1b = 1, and c=2c = 2. Your working must include: - use of the maximum and minimum values to find aa and cc - use of the period to find bb [3 marks]
(b)
Hence, find all values of xx in 0x2π0 \leq x \leq 2\pi that satisfy 3cosx+2=123\cos x + 2 = \dfrac{1}{2}, giving your answers in exact form. [2 marks]
(c)
The line y=ky = k intersects the graph of y=3cosx+2y = 3\cos x + 2 at exactly one point in the open interval 0<x<2π0 < x < 2\pi. Determine the value of kk and the corresponding xx-value. [2 marks]
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18ChallengeSAQ-LSine, cosine, and tangent functionss10 marksPaper 1~15 min
A water wheel of radius 55 metres rotates anticlockwise at a constant angular speed. The point PP is located at the lowest point on the wheel at time t=0t = 0 seconds. The height h(t)h(t) metres of PP above the water level is modelled by h(t)=asin(bt)+c,t0h(t) = a\sin(bt) + c, \quad t \geq 0 After 22 seconds, PP reaches its maximum height of 88 metres for the first time.
(a)
Write down the values of aa and cc[2 marks]
(b)
Show that b=π4b = \dfrac{\pi}{4}[2 marks]
(c)
Find the first time t>0t > 0 at which h(t)=2h(t) = 2, giving your answer correct to three significant figures. [3 marks]
(d)
The wheel is submerged whenever h(t)<0h(t) < 0. Determine the total length of time, per complete revolution, for which PP is below the water level. Give your answer in exact form. [3 marks]
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19FoundationSAQ-SSine, cosine, and tangent functionss5 marksPaper 1~8 min
A ladder of length 55 metres leans against a vertical wall. The angle between the ladder and the ground is θ\theta, where 0<θ<π20 < \theta < \dfrac{\pi}{2}. The horizontal distance from the base of the ladder to the wall is xx metres and the vertical height reached by the ladder is hh metres.
(a)
Show that x=5cosθx = 5\cos\theta[1 mark]
(b)
Given that sinθ=35\sin\theta = \dfrac{3}{5}, find the exact value of xx[2 marks]
(c)
Find the exact area of the triangle formed by the ladder, the wall, and the ground. [2 marks]
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20MasterySAQ-SSine, cosine, and tangent functionss5 marksPaper 1~8 min
Consider the function f(x)=acosx+bf(x) = a\cos x + b, where aa and bb are constants. The graph of y=f(x)y = f(x) passes through the points (0,5)(0,\,5) and (π,1)(\pi,\,-1).
(a)
Show that a=3a = 3 and b=2b = 2[3 marks]
(b)
Hence, find the exact value of f ⁣(π3)f\!\left(\dfrac{\pi}{3}\right)[2 marks]
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21MasterySAQ-SReal-world applications of functions (e.g. growth models)s8 marksPaper 2~12 min
The population of a small town is growing linearly. In 2015, the population was 1240012\,400 people. In 2023, the population was 1420014\,200 people. Let PP represent the population tt years after 2015.
(a)
Find the linear function P(t)P(t) that models the population growth. [3 marks]
(b)
Using your model, determine the year in which the population will reach 1600016\,000 people. [2 marks]
(c)
The town has a maximum sustainable population of 1800018\,000 people. Determine the year in which the model predicts this limit will be reached, and evaluate one reason why the linear model may not be reliable for this prediction. [3 marks]
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22MasterySAQ-SReal-world applications of functions (e.g. growth models)s6 marksPaper 2~9 min
A biologist is studying the growth of a bacterial culture. The number of bacteria, NN, after tt hours is modelled by N(t)=500ektN(t) = 500\,e^{kt}, where kk is a positive constant. After 33 hours there are 12001200 bacteria.
(a)
Find the value of kk, correct to three significant figures. [3 marks]
(b)
Find the time at which the number of bacteria first exceeds 1000010\,000, giving your answer correct to the nearest minute. [3 marks]
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23MasterySAQ-SReal-world applications of functions (e.g. growth models)s8 marksPaper 2~12 min
A biologist is studying the growth of a bacterial colony. At 09:00, the colony has an area of 8.0cm28.0\,\text{cm}^2. The area of the colony increases by a constant amount each hour. At 14:00, the area is 21.5cm221.5\,\text{cm}^2.
(a)
Calculate the constant hourly increase in area. [2 marks]
(b)
Find the area of the colony at 18:00. [2 marks]
(c)
A second model proposes that the area grows exponentially, with the same values at 09:00 and 14:00. Determine the ratio of the area predicted by the exponential model to the area predicted by the linear model at 18:00, and hence evaluate which model predicts faster growth over the interval 09:00 to 18:00. [4 marks]
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24MasterySAQ-SReal-world applications of functions (e.g. growth models)s6 marksPaper 2~9 min
The amount AA (in grams) of a radioactive substance remaining after tt hours is modelled by A(t)=A0eλtA(t) = A_0 e^{-\lambda t}. The graph of AA against tt passes through the points (0,240)(0,\,240) and (10,120)(10,\,120).
(a)
Show that λ=ln210\lambda = \dfrac{\ln 2}{10}[2 marks]
(b)
Calculate the value of λ\lambda correct to three significant figures. [1 mark]
(c)
The substance becomes safe to handle when its amount falls below 15g15\,\text{g}. Using your value of λ\lambda from part (b), determine the time at which the substance first becomes safe to handle. Give your answer correct to the nearest hour. [3 marks]
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25MasterySAQ-SReal-world applications of functions (e.g. growth models)s6 marksPaper 2~9 min
A city's population is growing linearly. In the year 2000, the population was 4500045\,000. In the year 2010, the population was 5400054\,000.
(a)
State the annual rate of population growth. [1 mark]
(b)
Calculate the population in the year 2025. [2 marks]
(c)
A second city has population model Q(t)=30000+1400tQ(t) = 30\,000 + 1\,400t, where tt is the number of years after 2000. Determine the year in which the two cities will have the same population, and state which city has the larger population in the year 2040. [3 marks]
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26MasterySAQ-SDefinition and types of functions (one-to-one, onto etc.)s6 marksPaper 2~9 min
A company designs a water tank. The volume of water in the tank, VV litres, at time tt hours after filling begins is modelled by V(t)=20001000e0.2t,t0.V(t) = 2000 - 1000e^{-0.2t}, \quad t \geq 0.
(a)
Determine the range of VV[2 marks]
(b)
The tank is considered full when the volume reaches 19001900 litres. Find the exact time, in hours, for the tank to become full, giving your answer in the form alnba\ln b where a,bQ+a, b \in \mathbb{Q}^+[2 marks]
(c)
Hence state the time for the tank to become full, correct to the nearest minute. [2 marks]
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27MasterySAQ-SDefinition and types of functions (one-to-one, onto etc.)s7 marksPaper 2~11 min
Consider the function g(x)=x24x+5g(x) = x^2 - 4x + 5, for xRx \in \mathbb{R}.
(a)
Write g(x)g(x) in the form a(xh)2+ka(x-h)^2 + k, where aa, hh, kZk \in \mathbb{Z}[1 mark]
(b)
Hence explain why gg is not a one-to-one function. [2 marks]
(c)
The domain of gg is restricted to xpx \geq p so that gg becomes one-to-one. State the minimum value of pp[1 mark]
(d)
For the restricted domain part (c), find g1(x)g^{-1}(x), stating its domain. [3 marks]
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28MasterySAQ-SDefinition and types of functions (one-to-one, onto etc.)s6 marksPaper 2~9 min
A function hh is defined by h(x)=2x1x+3h(x) = \dfrac{2x-1}{x+3}, for xR, x3x \in \mathbb{R},\ x \neq -3.
(a)
Justify that hh is a one-to-one function. [2 marks]
(b)
The codomain of hh is R{c}\mathbb{R} \setminus \{c\}. Find the value of cc[2 marks]
(c)
Hence, calculate the value of h1(5)h^{-1}(5)[2 marks]
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29MasterySAQ-SDefinition and types of functions (one-to-one, onto etc.)s8 marksPaper 2~12 min
The function ff is defined by f(x)=ln(x24x+5)f(x) = \ln(x^2 - 4x + 5), for xRx \in \mathbb{R}.
(a)
Determine the domain of ff[2 marks]
(b)
Show that ff is not a one-to-one function. [2 marks]
(c)
The domain of ff is restricted to x2x \geq 2 so that ff becomes one-to-one. Find an expression for f1(x)f^{-1}(x), stating its domain. [4 marks]
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30MasterySAQ-SDefinition and types of functions (one-to-one, onto etc.)s6 marksPaper 2~9 min
A company designs a logo consisting of a curve and a line. The curve is modelled by f(x)=x2+4x+5f(x) = -x^2 + 4x + 5 for 0x50 \leq x \leq 5. The line is modelled by g(x)=2x+1g(x) = 2x + 1 for 0x40 \leq x \leq 4.
(a)
Determine whether ff is a one-to-one function the given domain. Justify your answer. [2 marks]
(b)
(i) Find the range of ff. [2]
(ii) Find the range of gg. Hence determine whether gg is surjective onto the range of ff, giving a specific counterexample if it is not. > [2 marks]
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31MasterySAQ-STranslation, reflection, stretching, and compressions13 marksPaper 2~20 min
The below shows the graph of y=f(x)y = f(x) for 4x4-4 \leq x \leq 4. The graph has a local maximum at A(2,5)A(-2,\,5) and a local minimum at B(1,3)B(1,\,-3). The graph of ff is transformed to obtain the graph of gg, where g(x)=2f(x+1)3g(x) = 2f(x+1) - 3.
(a)
Calculate the coordinates of the images of AA and BB on the graph of gg[4 marks]
(b)
The function ff has a horizontal asymptote at y=0y = 0. Write down the equation of the horizontal asymptote of gg[1 mark]
(c)
Determine the range of values of xx for which g(x)>0g(x) > 0, given that gg has exactly two zeros and that the zero with the larger xx-value lies between the images of AA and BB found in part (a). Justify your answer. [1] Revised (c) — replacing trivial reflection with genuine AO3 discriminator: (c) The graph of gg is further transformed by the mapping (x,y)(x,y+k)(x,\,y) \mapsto (x,\,-y+k) for some constant kk. The image of AA' under this combined transformation has the same yy-coordinate as the image of BB'. Find the value of kk. [1] Final clean version: (a) Calculate the coordinates of the images of AA and BB on the graph of gg. [4] (b) The function ff has a horizontal asymptote at y=0y = 0. Write down the equation of the horizontal asymptote of gg. [1] (c) The graph of gg is reflected in the xx-axis to give the graph of hh. The graph of hh is then translated by (0k)\begin{pmatrix}0\\k\end{pmatrix} so that the image of AA' and the image of BB' have the same yy-coordinate. Find the value of kk[1 mark]
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32MasterySAQ-STranslation, reflection, stretching, and compressions7 marksPaper 2~11 min
The graph of y=f(x)y = f(x) consists of a straight line segment from A(4,2)A(-4, -2) to B(0,2)B(0, 2), and another straight line segment from B(0,2)B(0, 2) to C(4,0)C(4, 0). The graph of ff is transformed to the graph of gg by a horizontal stretch by scale factor 22, followed by a reflection in the yy-axis, followed by a translation by the vector (10)\begin{pmatrix} 1 \\ 0 \end{pmatrix}.
(a)
Calculate the coordinates of the images of AA, BB, and CC under this composite transformation. [3 marks]
(b)
Calculate the gradient of the image of segment BCBC on the graph of gg[2 marks]
(c)
Hence find the equation of the image of segment ABAB on the graph of gg, giving your answer in the form y=mx+cy = mx + c[2 marks]
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33MasterySAQ-STranslation, reflection, stretching, and compressions6 marksPaper 2~9 min
The graph of y=f(x)y = f(x) has a local maximum at (2,5)(-2,\,5) and a local minimum at (1,3)(1,\,-3). The curve passes through (0,1)(0,\,1). The function gg is defined by g(x)=f(2x)4.g(x) = f(2x) - 4.
(a)
Determine the coordinates of the local maximum and local minimum of gg[4 marks]
(b)
The graph of gg crosses the yy-axis at the point PP. Write down the coordinates of PP, and hence state the number of xx-intercepts of gg that lie in the interval 1x1-1 \leq x \leq 1[2 marks]
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34MasterySAQ-STranslation, reflection, stretching, and compressions6 marksPaper 2~9 min
The graph of y=f(x)y = f(x) for 4x4-4 \leq x \leq 4 is shown below. It has xx-intercepts at x=3x = -3, x=0x = 0, and x=2x = 2. The function gg is obtained from ff by the following sequence of transformations: - a vertical compression with scale factor 12\dfrac{1}{2}, - followed by a reflection in the xx-axis, - followed by a translation of 33 units in the positive xx-direction.
(a)
Determine the xx-intercepts of the graph of gg[3 marks]
(b)
The function ff has a local maximum at (1.5,  2)(-1.5,\; 2). Calculate the coordinates of the corresponding point on the graph of gg[3 marks]
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35MasterySAQ-STranslation, reflection, stretching, and compressions6 marksPaper 2~9 min
The function ff is defined by f(x)=x24x+5f(x) = x^2 - 4x + 5 for xRx \in \mathbb{R}.
(a)
Express f(x)f(x) in the form (xh)2+k(x - h)^2 + k, where h,kZh, k \in \mathbb{Z}[2 marks]
(b)
The graph of ff is translated by the vector (23)\begin{pmatrix} 2 \\ -3 \end{pmatrix} to give the graph of gg. Find an expression for g(x)g(x) in the form (xa)2+b(x - a)^2 + b, where a,bZa, b \in \mathbb{Z}[2 marks]
(c)
The graph of gg is reflected in the xx-axis to give the graph of pp, where p(x)=(x4)2+2p(x) = -(x-4)^2 + 2. Determine the number of intersections between the graphs of gg and pp, justifying your answer. [2 marks]
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36MasterySAQ-SSine, cosine, and tangent functionss7 marksPaper 2~11 min
A Ferris wheel at a theme park has a diameter of 4040 metres. The lowest point of the wheel is 22 metres above the ground. The wheel completes one full revolution in 6060 seconds. A rider starts at the lowest point at time t=0t = 0 seconds. The height h(t)h(t) metres of the rider above the ground after tt seconds is modelled by h(t)=acos(bt)+ch(t) = a\cos(bt) + c where aa, bb, and cc are constants.
(a)
State the value of aa[1 mark]
(b)
Calculate the value of bb[2 marks]
(c)
State the value of cc[1 mark]
(d)
Calculate the height of the rider after 2525 seconds. Give your answer correct to 3 significant figures. [3 marks]
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37MasterySAQ-SSine, cosine, and tangent functionss6 marksPaper 2~9 min
The depth of water in a harbour varies sinusoidally over time due to tides. At low tide at 4:00 AM, the depth is 33 metres. At high tide at 10:00 AM, the depth is 1111 metres. The depth d(t)d(t) metres at time tt hours after midnight is modelled by d(t)=Asin(B(tC))+Dd(t) = A\sin(B(t - C)) + D where AA, BB, CC, DD are constants.
(a)
State the value of AA[1 mark]
(b)
Calculate the value of BB[2 marks]
(c)
State the value of DD[1 mark]
(d)
Calculate the depth of water at 2:00 PM. Give your answer correct to 3 significant figures. [2 marks]
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Solutions

38MasterySAQ-SSine, cosine, and tangent functionss6 marksPaper 2~9 min
The voltage V(t)V(t) in an electrical circuit is modelled by V(t)=240sin(100πt)V(t) = 240\sin(100\pi t), where tt is time in seconds and VV is in volts.
(a)
State the amplitude of the voltage. [1 mark]
(b)
State the period of the voltage. [1 mark]
(c)
Calculate the voltage when t=0.0025t = 0.0025 seconds. Give your answer in exact form. [2 marks]
(d)
Determine the smallest positive value of tt for which V(t)=120V(t) = 120 volts. Give your answer in exact form. [2 marks]
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Solutions

39MasterySAQ-SSine, cosine, and tangent functionss6 marksPaper 2~9 min
A point on a bicycle tyre traces a circular path as the bicycle moves forward. Its height above the ground is modelled by h(θ)=35+35sin ⁣(θπ2)h(\theta) = 35 + 35\sin\!\left(\theta - \frac{\pi}{2}\right) where hh is in centimetres and θ\theta is the total angle, in radians, through which the tyre has rotated from its starting position.
(a)
Show that h(θ)h(\theta) can be written as h(θ)=3535cosθh(\theta) = 35 - 35\cos\theta[2 marks]
(b)
State the maximum height of the point above the ground and find the smallest positive value of θ\theta at which this maximum occurs. [2 marks]
(c)
Determine the first positive value of θ\theta for which h=52.5cmh = 52.5\,\text{cm}. Give your answer correct to 3 significant figures. [2 marks]
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40MasterySAQ-SSine, cosine, and tangent functionss7 marksPaper 2~11 min
The number of visitors to a museum on a particular day is modelled by N(t)=500+300sin ⁣(π12(t9))N(t) = 500 + 300\sin\!\left(\dfrac{\pi}{12}(t - 9)\right), where tt is the number of hours after midnight. The museum is open from 9:00 AM to 5:00 PM.
(a)
State the maximum number of visitors predicted by the model. [1 mark]
(b)
Calculate the time at which this maximum occurs. Give your answer in hours and minutes. [2 marks]
(c)
Calculate the number of visitors at 1:00 PM, giving your answer correct to the nearest whole number. [2 marks]
(d)
Determine the first time after opening when the number of visitors equals 650. Give your answer in hours and minutes. [2 marks]
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Solutions