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Chap 1: Sec. 1.2-Sec. 1.5:

1. Let f (x) =

|x + 2| for x ≤ 0;

2 + x2 for 0 < x < 2;

x3 for x≥ 2

. Find (a) limx→0f (x), (b)limx→0+f (x), (c) limx→2f (x), (d)limx→2+f (x), (e) limx→0f (x), (f) limx→2f (x) .

Ans: (a) 2 (b) 2 (c) 6 (d) 8 (e) 2 (f) DNE

2. Let f (x) = {

cx− 2 for x≤ 2;

cx2+ 2 for x > 2 Find c such that f (x) is continuous. Ans: c =−2 3. Determine the intervals on which f (x) = ln (1− x2) is continuous.

Ans: 1− x2> 0 or (−1, 1) 4. Compute (i) limx→0

x+9−3

x (ii) limx→1 2x x2−1

Ans: (i) 6 (ii)−∞

Chap 2: Sec. 2.3-Sec. 2.9:

1. Find the tangent line to the curve y = x3− 4x2+ 2x + 1 at the point (1, 0).

Ans: dydx = 3x2− 8x + 2; slope=−3; y − 0 = −3(x − 1) 2. Let y = ex2 · (x2+ x + 1)·√

3x + 1/(x2− 1). Find dydx. Hint: Take “ln” on both side.

3. The equation 7x2y3− 5xy2− 4y = 7 defines y implicitly as a function of x. Find dxdy. Ans:4+10xy14xy3−21x−5y22y2

4. Find the derivative of (i) f (x) = x2x; (ii) g(x) = x3x+12−x; (iii) h(x) = ln

3x+1

5x+2 (assuming 3x + 1 > 0)

Ans: (i)2(ln x + 1)x2x;(ii) (2x−1)(3x+1)−(x2−x)(3)

(3x+1)2 = (3x(3x+1)−1)(x+1)2 ; (iii)= 12(3x+13 5x+25 )

5. Determine if f (x) = x7+ 2x3− 2006 is increasing, decreasing or neither. Prove f(x) = 0 has exactly one solution. Hint: Sec. 2.9 example 9.1

Chap 3: Sec. 3.1-Sec. 3.8:

1. Estimate 3

8.02 by the method of linear approximation (i.e., by differentials).

Ans: f (x) = x1/3;f (x)≈ f(8) + f0(8)(x− 8);√3

8.02≈ 2 +121(0.02)≈ 2.001667 2. Find the asymptotes of

(i) f (x) = (3x9x−1)2−42. Ans: V:x = 2/3, x =−2/3; H:y = 1 (ii) f (x) = (3x9x−1)2−12.Ans: V:x =−1/3; H:y = 1

(iii)f (x) = (3xx−1)−12 Ans: V:x = 1; H:none; S:y = 9x + 3.

3. Let f (x) = 2x3− 3x2− 12x. Find the relative extrema of f(x).

Ans: local max at x =−1; local min at x = 2; no abs. max/min

4. Find the absolute maximum and minimum values of the function f (x) = 2x3− 9x2+ 12x over the interval [0, 2]. Ans: Abs max: f (1) = 5; abs min: f (0) = 0

5. Determine the concavity of f (x) = 4x3− x4.

Ans: Concave up: (−∞, 0) ∪ (2, ∞); Concave down: (0, 2)

(2)

6. If 300 cm2 of material is available to make a box with square base and an open top, find the largest possible volume of the box. Explain why your answer is the absolute maximum.

Hint:example 6.2

7. Sketch the graph of the continuous function f that satisfies the conditions:

f00(x) > 0 if|x| > 2, f00(x) < 0 if|x| < 2;

f0(0) = 0, f0(x) > 0, if x < 0, f0(x) < 0, if x > 0;

f (0) = 1, f (2) = 1

2, f (x) > 0 for all x, and f is and even function.

Ans: The graph looks like e−x2/8

8. An automobile dealer is selling cars at a price of $12,000. The demand function is D(p) = 2(15− 0.001p)2, where p is the price of a car. Should the dealer raise or lower the price to increase the revenue? Hint: Find the derivative of the revenue function, R(p) = p· D(p) 9. Compute:

(i) limx→0(ln(x+1)1 1x); (ii) limx→1+ (xln x−1)2

Ans (i) Sec 3.2 example 2.7 (ii) Sec 3.2 exercise 38 Chap 4: Sec. 4.2-Sec. 4.8 (Integration Tables), 4.10,

1. Let f (x) = x + 1

(a) Divide the interval [0, 5] into n equal parts, and using right endpoints find an expression for the Riemann sum Rn.

Hint: 1 + 2 + ... + n = n(n+1)2

(b) Using the answer you got from part(a), calculate lim

n→∞Rn(without using antiderivatives).

2. Evaluate the given integral (i) x(x + 1)9dx, Hint:u = x + 1 (ii) dx

ex

4+e2x. Hint: u = ex,積分表 (iii) ln x

x

1+ln xdx, Hint:u = ln x (iv) x3

x2+1dx. Hint: u = 1 + x2

3. Evaluate the given integral (i)

xexdx =?; (ii) ln xx dx =?; (iii) x+4x dx =?; (iv)(ln x)2dx =?;

Hint: (i) u =√

x;(ii) u = ln x; (iii) = x− 4 ln |x + 4|; (iv) u = (ln x)2;dv = dx 4. Evaluate the given integral

(i) ln xx dx =?; (ii)ln (x2) dx =?; (iii) x2−3x−43x dx =?; (iv) x−2x3+2x2+42+xdx =?

Hint: (i) u = ln x;(ii)u = ln x2;dv = dx; (iii) x2− 3x − 4 = (x − 4)(x + 1);

(iv) x3+ 2x2+ x = x(x + 1)2 5. Evaluate the definite integrals:

(i) 14

xexdx =?; (ii)1e(ln x)2dx =?;

6. Evaluate the given integral

i)−∞ (1+ee−x−x)2 dx −∞ x3dx iii) limR→∞−RR x3dx Ans: (i) 1 (ii) DIV (iii) 0

7. Determine whether the integral converges or diverges:

i)01x−1/3dx ii)01x−4/3dx iii) 1x−1/3dx iv)−11 x−1/3dx Ans: (i) 3/2 (ii) DIV (iii) DIV (iv) 0

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