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Secondary 3 Additional Mathematics Calculus Quiz

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Questions

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Secondary 3 Additional Mathematics Quiz - Calculus

Name: ___________________________
Class: ___________________________
Date: ___________________________
Score: ________ / 50

Duration: 60 minutes
Total Marks: 50

Instructions:

  • Answer ALL questions.
  • Show all working clearly. Marks will be awarded for correct method even if the final answer is wrong.
  • Non-programmable scientific calculators may be used.
  • Give answers as exact values unless otherwise stated.
  • The number of marks for each question is shown in brackets [ ].

Section A: Differentiation (Questions 1–10)

Questions 1–5 are multiple choice. Shade the correct option on your answer sheet. Each question carries 2 marks.


1. Given that y=3x42x2+7y = 3x^4 - 2x^2 + 7, find dydx\frac{dy}{dx}.

A) 12x34x12x^3 - 4x
B) 12x34x+712x^3 - 4x + 7
C) 3x32x3x^3 - 2x
D) 12x32x12x^3 - 2x

 


2. If f(x)=(2x5)3f(x) = (2x - 5)^3, find f(x)f'(x).

A) 3(2x5)23(2x - 5)^2
B) 6(2x5)26(2x - 5)^2
C) 2(2x5)32(2x - 5)^3
D) 6(2x5)36(2x - 5)^3

 


3. Given y=x2+1xy = \frac{x^2 + 1}{x}, find dydx\frac{dy}{dx}.

A) 11x21 - \frac{1}{x^2}
B) 1+1x21 + \frac{1}{x^2}
C) 2x1x22x - \frac{1}{x^2}
D) 2x+1x22x + \frac{1}{x^2}

 


4. The equation of a curve is y=x36x2+9xy = x^3 - 6x^2 + 9x. At which point does the gradient equal zero?

A) (1,4)(1, 4) only
B) (3,0)(3, 0) only
C) (1,4)(1, 4) and (3,0)(3, 0)
D) (0,0)(0, 0) and (3,0)(3, 0)

 


5. A particle moves along a straight line such that its displacement, ss metres, from a fixed point OO at time tt seconds is given by s=t34t2+2ts = t^3 - 4t^2 + 2t. Find the velocity when t=3t = 3.

A) 5 m/s5 \text{ m/s}
B) 11 m/s11 \text{ m/s}
C) 5 m/s-5 \text{ m/s}
D) 3 m/s3 \text{ m/s}

 


Questions 6–10 are short-answer. Show your working clearly.


6. Differentiate each of the following with respect to xx:

(a) y=5x34x+3y = 5x^3 - 4x + 3
 

(b) y=(3x+2)(x4)y = (3x + 2)(x - 4)
 

(c) y=2x31x2y = \frac{2x^3 - 1}{x^2}
 

 


7. Given y=4x+1y = \sqrt{4x + 1}, find dydx\frac{dy}{dx}. Express your answer in surd form.
 

 


8. Find the gradient of the curve y=2x35x2+3x1y = 2x^3 - 5x^2 + 3x - 1 at the point where x=2x = 2.
 

 


9. Given f(x)=(x23)4f(x) = (x^2 - 3)^4, find f(1)f'(1).
 

 


10. A curve has equation y=ax3+bxy = ax^3 + bx. The gradient of the curve at the point (1,5)(1, 5) is 88. Find the values of aa and bb.
 

 


Section B: Applications of Differentiation (Questions 11–15)


11. The equation of a curve is y=x36x2+9x+2y = x^3 - 6x^2 + 9x + 2.

(a) Find dydx\frac{dy}{dx}.
 

(b) Find the coordinates of the stationary points of the curve.
 

(c) Determine the nature of each stationary point.
 

 


12. A rectangular enclosure is to be fenced using 120 m120 \text{ m} of fencing. One side of the enclosure is along a wall and requires no fencing.

(a) If the side perpendicular to the wall has length xx metres, show that the area enclosed is A=120x2x2A = 120x - 2x^2.
 

(b) Find the value of xx that maximises the enclosed area.
 

(c) Hence find the maximum area.
 

 


13. The curve y=x3+ax2+bx+cy = x^3 + ax^2 + bx + c has a stationary point at (2,5)(2, -5) and passes through the point (0,3)(0, 3). Find the values of aa, bb, and cc.
 

 


14. A particle moves in a straight line such that its displacement, ss metres, from the origin OO at time tt seconds is given by s=2t315t2+24t+3s = 2t^3 - 15t^2 + 24t + 3, for t0t \geq 0.

(a) Find an expression for the velocity vv of the particle at time tt.
 

(b) Find the times when the particle is instantaneously at rest.
 

(c) Find the acceleration of the particle when t=2t = 2.
 

 


15. The normal to the curve y=x24x+7y = x^2 - 4x + 7 at the point P(3,4)P(3, 4) meets the curve again at the point QQ. Find the coordinates of QQ.
 

 


Section C: Integration (Questions 16–20)


16. Find each of the following integrals:

(a) (6x24x+1)dx\int (6x^2 - 4x + 1) \, dx
 

(b) (2x3)2dx\int (2x - 3)^2 \, dx
 

(c) x31x2dx\int \frac{x^3 - 1}{x^2} \, dx
 

 


17. Given that dydx=3x26x+2\frac{dy}{dx} = 3x^2 - 6x + 2 and that y=5y = 5 when x=1x = 1, find yy in terms of xx.
 

 


18. Find the equation of the curve which passes through the point (2,10)(2, 10) and for which dydx=4x36x\frac{dy}{dx} = 4x^3 - 6x.
 

 


19. The gradient of a curve at any point (x,y)(x, y) is given by dydx=(x2)(x+3)\frac{dy}{dx} = (x - 2)(x + 3).

(a) Find the xx-coordinates of the stationary points of the curve.
 

(b) Given that the curve passes through the point (1,6)(1, 6), find the equation of the curve.
 

 


20. The velocity of a particle travelling in a straight line is given by v=3t212t+9 m/sv = 3t^2 - 12t + 9 \text{ m/s}, where t0t \geq 0 is the time in seconds.

(a) Given that the displacement s=5 ms = 5 \text{ m} when t=0t = 0, find an expression for ss in terms of tt.
 

(b) Find the displacement of the particle when t=3t = 3.
 

(c) Find the total distance travelled by the particle in the first 44 seconds.
 

 


END OF QUIZ

Answers

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Secondary 3 Additional Mathematics Quiz - Calculus

Answer Key


Section A: Differentiation (Questions 1–10)


1. A) 12x34x12x^3 - 4x [2]

Working: dydx=3(4)x32(2)x=12x34x\frac{dy}{dx} = 3(4)x^3 - 2(2)x = 12x^3 - 4x. The derivative of the constant 77 is zero.

Common mistake: Choosing B — forgetting that the derivative of a constant is zero.


2. B) 6(2x5)26(2x - 5)^2 [2]

Working: Using the chain rule: f(x)=3(2x5)2×2=6(2x5)2f'(x) = 3(2x - 5)^2 \times 2 = 6(2x - 5)^2.

Common mistake: Choosing A — forgetting to multiply by the derivative of the inner function (2x5)(2x - 5), which is 22.


3. A) 11x21 - \frac{1}{x^2} [2]

Working: Rewrite y=x2x+1x=x+x1y = \frac{x^2}{x} + \frac{1}{x} = x + x^{-1}. Then dydx=1x2=11x2\frac{dy}{dx} = 1 - x^{-2} = 1 - \frac{1}{x^2}.

Alternative: Using the quotient rule: dydx=(2x)(x)(x2+1)(1)x2=2x2x21x2=x21x2=11x2\frac{dy}{dx} = \frac{(2x)(x) - (x^2+1)(1)}{x^2} = \frac{2x^2 - x^2 - 1}{x^2} = \frac{x^2 - 1}{x^2} = 1 - \frac{1}{x^2}.


4. C) (1,4)(1, 4) and (3,0)(3, 0) [2]

Working: dydx=3x212x+9=3(x24x+3)=3(x1)(x3)\frac{dy}{dx} = 3x^2 - 12x + 9 = 3(x^2 - 4x + 3) = 3(x-1)(x-3). Setting dydx=0\frac{dy}{dx} = 0: x=1x = 1 or x=3x = 3. When x=1x = 1: y=16+9=4y = 1 - 6 + 9 = 4. When x=3x = 3: y=2754+27=0y = 27 - 54 + 27 = 0. Points are (1,4)(1, 4) and (3,0)(3, 0).


5. A) 5 m/s5 \text{ m/s} [2]

Working: v=dsdt=3t28t+2v = \frac{ds}{dt} = 3t^2 - 8t + 2. When t=3t = 3: v=3(9)8(3)+2=2724+2=5 m/sv = 3(9) - 8(3) + 2 = 27 - 24 + 2 = 5 \text{ m/s}.


6.

(a) dydx=15x24\frac{dy}{dx} = 15x^2 - 4 [1]

Working: ddx(5x3)ddx(4x)+ddx(3)=15x24+0\frac{d}{dx}(5x^3) - \frac{d}{dx}(4x) + \frac{d}{dx}(3) = 15x^2 - 4 + 0.

(b) dydx=6x10\frac{dy}{dx} = 6x - 10 [2]

Working: First expand: y=3x212x+2x8=3x210x8y = 3x^2 - 12x + 2x - 8 = 3x^2 - 10x - 8. Then dydx=6x10\frac{dy}{dx} = 6x - 10.

Alternative using product rule: dydx=(3)(x4)+(3x+2)(1)=3x12+3x+2=6x10\frac{dy}{dx} = (3)(x-4) + (3x+2)(1) = 3x - 12 + 3x + 2 = 6x - 10.

(c) dydx=2+2x3\frac{dy}{dx} = 2 + \frac{2}{x^3} [2]

Working: Rewrite y=2x3x21x2=2xx2y = \frac{2x^3}{x^2} - \frac{1}{x^2} = 2x - x^{-2}. Then dydx=2(2)x3=2+2x3\frac{dy}{dx} = 2 - (-2)x^{-3} = 2 + \frac{2}{x^3}.


7. dydx=24x+1\frac{dy}{dx} = \frac{2}{\sqrt{4x+1}} [3]

Working: y=(4x+1)1/2y = (4x+1)^{1/2}. Using the chain rule: dydx=12(4x+1)1/2×4=24x+1\frac{dy}{dx} = \frac{1}{2}(4x+1)^{-1/2} \times 4 = \frac{2}{\sqrt{4x+1}}.

Marking: [1] for correct application of chain rule, [1] for correct simplification, [1] for final answer in surd form.


8. Gradient =3= 3 [3]

Working: dydx=6x210x+3\frac{dy}{dx} = 6x^2 - 10x + 3. At x=2x = 2: dydx=6(4)10(2)+3=2420+3=7\frac{dy}{dx} = 6(4) - 10(2) + 3 = 24 - 20 + 3 = 7.

Correction: dydx=6(4)20+3=2420+3=7\frac{dy}{dx} = 6(4) - 20 + 3 = 24 - 20 + 3 = 7.

Gradient =7= 7 [3]

Marking: [1] for correct differentiation, [1] for correct substitution, [1] for correct evaluation.


9. f(1)=32f'(1) = -32 [3]

Working: f(x)=4(x23)3×2x=8x(x23)3f'(x) = 4(x^2 - 3)^3 \times 2x = 8x(x^2 - 3)^3. At x=1x = 1: f(1)=8(1)(13)3=8(2)3=8(8)=64f'(1) = 8(1)(1 - 3)^3 = 8(-2)^3 = 8(-8) = -64.

Correction: f(1)=8(1)(13)3=8(1)(8)=64f'(1) = 8(1)(1-3)^3 = 8(1)(-8) = -64.

f(1)=64f'(1) = -64 [3]

Marking: [1] for correct chain rule application, [1] for correct substitution, [1] for correct evaluation.


10. a=132a = \frac{13}{2}, b=32b = -\frac{3}{2} [4]

Working: y=ax3+bxy = ax^3 + bx, so dydx=3ax2+b\frac{dy}{dx} = 3ax^2 + b. At (1,5)(1, 5): y=a(1)3+b(1)=a+b=5y = a(1)^3 + b(1) = a + b = 5 … (i). Gradient: 3a(1)2+b=3a+b=83a(1)^2 + b = 3a + b = 8 … (ii). Subtracting (i) from (ii): 2a=32a = 3, so a=32a = \frac{3}{2}. From (i): 32+b=5\frac{3}{2} + b = 5, so b=72b = \frac{7}{2}.

Correction: From (ii) − (i): (3a+b)(a+b)=85=3(3a + b) - (a + b) = 8 - 5 = 3, so 2a=32a = 3, a=32a = \frac{3}{2}. Then b=532=72b = 5 - \frac{3}{2} = \frac{7}{2}.

a=32a = \frac{3}{2}, b=72b = \frac{7}{2} [4]

Marking: [1] for correct differentiation, [1] for forming equation from point on curve, [1] for forming equation from gradient, [1] for solving simultaneously.


Section B: Applications of Differentiation (Questions 11–15)


11.

(a) dydx=3x212x+9\frac{dy}{dx} = 3x^2 - 12x + 9 [1]

(b) Stationary points: (1,6)(1, 6) and (3,2)(3, 2) [3]

Working: Set dydx=0\frac{dy}{dx} = 0: 3x212x+9=03x^2 - 12x + 9 = 0, so x24x+3=0x^2 - 4x + 3 = 0, giving (x1)(x3)=0(x-1)(x-3) = 0, so x=1x = 1 or x=3x = 3. When x=1x = 1: y=16+9+2=6y = 1 - 6 + 9 + 2 = 6. When x=3x = 3: y=2754+27+2=2y = 27 - 54 + 27 + 2 = 2. Points are (1,6)(1, 6) and (3,2)(3, 2).

Marking: [1] for solving dydx=0\frac{dy}{dx}=0, [1] for each correct point.

(c) At x=1x = 1: maximum; at x=3x = 3: minimum [3]

Working: d2ydx2=6x12\frac{d^2y}{dx^2} = 6x - 12. At x=1x = 1: d2ydx2=612=6<0\frac{d^2y}{dx^2} = 6 - 12 = -6 < 0, so maximum. At x=3x = 3: d2ydx2=1812=6>0\frac{d^2y}{dx^2} = 18 - 12 = 6 > 0, so minimum.

Marking: [1] for correct second derivative, [1] for correct nature at x=1x=1, [1] for correct nature at x=3x=3.


12.

(a) Shown. [2]

Working: Let the two sides perpendicular to the wall each have length xx and the side parallel to the wall have length ll. Then l+2x=120l + 2x = 120, so l=1202xl = 120 - 2x. Area A=l×x=(1202x)x=120x2x2A = l \times x = (120 - 2x)x = 120x - 2x^2.

Marking: [1] for correct expression for ll, [1] for correct area expression.

(b) x=30x = 30 [2]

Working: dAdx=1204x\frac{dA}{dx} = 120 - 4x. Set dAdx=0\frac{dA}{dx} = 0: 1204x=0120 - 4x = 0, so x=30x = 30. Check: d2Adx2=4<0\frac{d^2A}{dx^2} = -4 < 0, confirming maximum.

Marking: [1] for differentiation and solving, [1] for confirming maximum.

(c) Maximum area =1800 m2= 1800 \text{ m}^2 [1]

Working: A=120(30)2(30)2=36001800=1800A = 120(30) - 2(30)^2 = 3600 - 1800 = 1800.


13. a=3a = -3, b=0b = 0, c=3c = 3 [5]

Working: dydx=3x2+2ax+b\frac{dy}{dx} = 3x^2 + 2ax + b. At stationary point (2,5)(2, -5): dydx=0\frac{dy}{dx} = 0 when x=2x = 2, so 3(4)+2a(2)+b=03(4) + 2a(2) + b = 0, giving 12+4a+b=012 + 4a + b = 0 … (i). Also y=5y = -5 when x=2x = 2: 8+4a+2b+c=58 + 4a + 2b + c = -5 … (ii). The curve passes through (0,3)(0, 3): c=3c = 3 … (iii). From (iii) into (ii): 8+4a+2b+3=58 + 4a + 2b + 3 = -5, so 4a+2b=164a + 2b = -16, i.e. 2a+b=82a + b = -8 … (iv). From (i): 4a+b=124a + b = -12 … (i). Subtracting (iv) from (i): 2a=42a = -4, so a=2a = -2. From (iv): 2(2)+b=82(-2) + b = -8, so b=4b = -4.

Correction: From (i): 4a+b=124a + b = -12. From (iv): 2a+b=82a + b = -8. Subtracting: 2a=42a = -4, so a=2a = -2. Then b=82(2)=8+4=4b = -8 - 2(-2) = -8 + 4 = -4. And c=3c = 3.

a=2a = -2, b=4b = -4, c=3c = 3 [5]

Marking: [1] for dydx=0\frac{dy}{dx}=0 at x=2x=2, [1] for point (2,5)(2,-5) on curve, [1] for c=3c=3, [1] for solving for aa, [1] for solving for bb.


14.

(a) v=6t230t+24v = 6t^2 - 30t + 24 [1]

Working: v=dsdt=6t230t+24v = \frac{ds}{dt} = 6t^2 - 30t + 24.

(b) t=1t = 1 and t=4t = 4 [3]

Working: Set v=0v = 0: 6t230t+24=06t^2 - 30t + 24 = 0, so t25t+4=0t^2 - 5t + 4 = 0, giving (t1)(t4)=0(t-1)(t-4) = 0. So t=1t = 1 or t=4t = 4.

Marking: [1] for setting v=0v=0, [1] for correct factorisation, [1] for both values.

(c) Acceleration =6 m/s2= -6 \text{ m/s}^2 [2]

Working: a=dvdt=12t30a = \frac{dv}{dt} = 12t - 30. At t=2t = 2: a=2430=6 m/s2a = 24 - 30 = -6 \text{ m/s}^2.

Marking: [1] for correct differentiation, [1] for correct substitution.


15. Q=(12,134)Q = \left(\frac{1}{2}, \frac{13}{4}\right) [5]

Working: dydx=2x4\frac{dy}{dx} = 2x - 4. At x=3x = 3: gradient of tangent =2(3)4=2= 2(3) - 4 = 2. Gradient of normal =12= -\frac{1}{2}. Equation of normal at (3,4)(3, 4): y4=12(x3)y - 4 = -\frac{1}{2}(x - 3), so y=12x+32+4=12x+112y = -\frac{1}{2}x + \frac{3}{2} + 4 = -\frac{1}{2}x + \frac{11}{2}. To find intersection with curve: x24x+7=12x+112x^2 - 4x + 7 = -\frac{1}{2}x + \frac{11}{2}. Multiply by 2: 2x28x+14=x+112x^2 - 8x + 14 = -x + 11, so 2x27x+3=02x^2 - 7x + 3 = 0. Factorise: (2x1)(x3)=0(2x - 1)(x - 3) = 0. So x=3x = 3 (point PP) or x=12x = \frac{1}{2}. When x=12x = \frac{1}{2}: y=142+7=214=134y = \frac{1}{4} - 2 + 7 = \frac{21}{4} = \frac{13}{4}... Let me recalculate: y=(12)24(12)+7=142+7=14+5=214y = \left(\frac{1}{2}\right)^2 - 4\left(\frac{1}{2}\right) + 7 = \frac{1}{4} - 2 + 7 = \frac{1}{4} + 5 = \frac{21}{4}.

Q=(12,214)Q = \left(\frac{1}{2}, \frac{21}{4}\right) [5]

Marking: [1] for gradient of tangent, [1] for gradient of normal, [1] for equation of normal, [1] for solving simultaneous equations, [1] for correct coordinates of QQ.


Section C: Integration (Questions 16–20)


16.

(a) (6x24x+1)dx=2x32x2+x+c\int(6x^2 - 4x + 1)\,dx = 2x^3 - 2x^2 + x + c [2]

Marking: [1] for correct integration of each term, [1] for including constant of integration.

(b) (2x3)2dx=(2x3)36+c\int(2x-3)^2\,dx = \frac{(2x-3)^3}{6} + c (or expanded form) [2]

Working (substitution): Let u=2x3u = 2x - 3, du=2dxdu = 2\,dx. u2du2=12u33=(2x3)36+c\int u^2 \cdot \frac{du}{2} = \frac{1}{2} \cdot \frac{u^3}{3} = \frac{(2x-3)^3}{6} + c.

Working (expansion): (2x3)2=4x212x+9(2x-3)^2 = 4x^2 - 12x + 9. (4x212x+9)dx=4x336x2+9x+c\int(4x^2 - 12x + 9)\,dx = \frac{4x^3}{3} - 6x^2 + 9x + c.

Marking: Either method accepted. [1] for correct method, [1] for correct answer with constant.

(c) x31x2dx=x22+1x+c\int\frac{x^3-1}{x^2}\,dx = \frac{x^2}{2} + \frac{1}{x} + c [2]

Working: x31x2=xx2\frac{x^3-1}{x^2} = x - x^{-2}. (xx2)dx=x22x11+c=x22+1x+c\int(x - x^{-2})\,dx = \frac{x^2}{2} - \frac{x^{-1}}{-1} + c = \frac{x^2}{2} + \frac{1}{x} + c.

Marking: [1] for correct simplification, [1] for correct integration with constant.


17. y=x33x2+2x+5y = x^3 - 3x^2 + 2x + 5 [4]

Working: y=(3x26x+2)dx=x33x2+2x+cy = \int(3x^2 - 6x + 2)\,dx = x^3 - 3x^2 + 2x + c. When x=1x = 1, y=5y = 5: 13+2+c=51 - 3 + 2 + c = 5, so c=5c = 5. Therefore y=x33x2+2x+5y = x^3 - 3x^2 + 2x + 5.

Marking: [1] for correct integration, [1] for including constant, [1] for correct substitution, [1] for correct value of cc and final expression.


18. y=x43x2+2y = x^4 - 3x^2 + 2 [4]

Working: y=(4x36x)dx=x43x2+cy = \int(4x^3 - 6x)\,dx = x^4 - 3x^2 + c. When x=2x = 2, y=10y = 10: 1612+c=1016 - 12 + c = 10, so c=6c = 6. Therefore y=x43x2+6y = x^4 - 3x^2 + 6.

Correction: 1612+c=1016 - 12 + c = 10, so 4+c=104 + c = 10, c=6c = 6.

y=x43x2+6y = x^4 - 3x^2 + 6 [4]

Marking: [1] for correct integration, [1] for including constant, [1] for correct substitution, [1] for correct final equation.


19.

(a) x=2x = 2 and x=3x = -3 [2]

Working: At stationary points, dydx=0\frac{dy}{dx} = 0: (x2)(x+3)=0(x-2)(x+3) = 0, so x=2x = 2 or x=3x = -3.

Marking: [1] for each correct value.

(b) y=x33+x226x+836y = \frac{x^3}{3} + \frac{x^2}{2} - 6x + \frac{83}{6} [4]

Working: y=(x2+x6)dx=x33+x226x+cy = \int(x^2 + x - 6)\,dx = \frac{x^3}{3} + \frac{x^2}{2} - 6x + c. When x=1x = 1, y=6y = 6: 13+126+c=6\frac{1}{3} + \frac{1}{2} - 6 + c = 6. So 566+c=6\frac{5}{6} - 6 + c = 6, giving c=6+656=1256=676c = 6 + 6 - \frac{5}{6} = 12 - \frac{5}{6} = \frac{67}{6}.

Correction: 13+12=56\frac{1}{3} + \frac{1}{2} = \frac{5}{6}. So 566+c=6\frac{5}{6} - 6 + c = 6, meaning c=1256=7256=676c = 12 - \frac{5}{6} = \frac{72-5}{6} = \frac{67}{6}.

y=x33+x226x+676y = \frac{x^3}{3} + \frac{x^2}{2} - 6x + \frac{67}{6} [4]

Marking: [1] for expanding the integrand, [1] for correct integration, [1] for correct substitution, [1] for correct final equation.


20.

(a) s=t36t2+9t+5s = t^3 - 6t^2 + 9t + 5 [2]

Working: s=(3t212t+9)dt=t36t2+9t+cs = \int(3t^2 - 12t + 9)\,dt = t^3 - 6t^2 + 9t + c. When t=0t = 0, s=5s = 5: c=5c = 5. So s=t36t2+9t+5s = t^3 - 6t^2 + 9t + 5.

Marking: [1] for correct integration with constant, [1] for correct value of cc.

(b) Displacement =5 m= 5 \text{ m} [2]

Working: s=2754+27+5=5 ms = 27 - 54 + 27 + 5 = 5 \text{ m}.

Marking: [1] for correct substitution, [1] for correct answer.

(c) Total distance =12 m= 12 \text{ m} [4]

Working: v=3t212t+9=3(t24t+3)=3(t1)(t3)v = 3t^2 - 12t + 9 = 3(t^2 - 4t + 3) = 3(t-1)(t-3). The velocity changes sign at t=1t = 1 and t=3t = 3. For 0<t<10 < t < 1: v>0v > 0 (particle moves forward). For 1<t<31 < t < 3: v<0v < 0 (particle moves backward). For 3<t<43 < t < 4: v>0v > 0 (particle moves forward). Displacement from t=0t = 0 to t=1t = 1: s(1)s(0)=(16+9+5)5=95=4 ms(1) - s(0) = (1 - 6 + 9 + 5) - 5 = 9 - 5 = 4 \text{ m}. Displacement from t=1t = 1 to t=3t = 3: s(3)s(1)=(2754+27+5)9=59=4 ms(3) - s(1) = (27 - 54 + 27 + 5) - 9 = 5 - 9 = -4 \text{ m} (distance =4 m= 4 \text{ m}). Displacement from t=3t = 3 to t=4t = 4: s(4)s(3)=(6496+36+5)5=95=4 ms(4) - s(3) = (64 - 96 + 36 + 5) - 5 = 9 - 5 = 4 \text{ m}. Total distance =4+4+4=12 m= 4 + 4 + 4 = 12 \text{ m}.

Marking: [1] for finding when v=0v = 0, [1] for determining sign changes/direction, [1] for calculating each stage of distance, [1] for correct total.


END OF ANSWER KEY