1. (15%) On the curve y3+ xy2+ x2y− 2x3= 1, use implicit differentiation to find (a)dydx and (b) the values of dydx, ddx2y2 at the point x= 1, y = 1.
2. (12%) Find the point on y2= 2x that is closest to the point (1, 4).
3. (21%) Let y= f(x) = 1+xx32. Answer the following questions. Fill each blank and give your reasons (and computations). Put None in the blank if the item asked does not exist.
(a) The function is increasing on the interval(s) (5%).
The local maximal point(s)(x, y) = .The local minimal point(s)(x, y) = .(2%
total)Reason:
(b) The function is concave upward on the interval(s) and concave downward
on the interval(s) .(5% total)
The inflection point(s)(x, y) = (2%). Reason: (c) The asymptote lines of the function are (3%). Reason:
(d) Sketch the graph of the function. Indicate, if any, where it is increasing/decreasing, where it concave upward/downward, all relative maxima/minima, inflection points and asymptotic line(s) (if any).(4%)
4. (10%) (a) Find the linear approximation of(1 + x)1/3 at x= 0.
(b) Use (a) to estimate √3 8.03.
5. (12%) Let f(x) = 3x − sin x.
(a) Prove that f(x) is an increasing function.
(b) Let g(x) be the inverse function of f(x). Find g′(0).
6. (20%) Evaluate y′. (a) y= 3cos x
(b) y= tan−1(1 + x2) (c) y= ln(x +√
1+ x2) (d) y=1+sin xcos x
7. (10%) Evaluate the following limits.
(a) lim
x→1+ ln x x−1
(b) lim
x→2
√
x3+x2−8−2 x−2
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