Homework # 11 - Math 149
The problems on this homework must be done alone. The honor code is in effect.
First name: Last name:
For problems 1 to 3, take the derivative.
1. \(f(x) = \sqrt{x} \sin x\)
a. \( f'(x) = \frac{\cos x}{2\sqrt{x}}\)
b. \( f'(x) = \frac{\sin x}{2\sqrt{x}}\)
c. \( f'(x) = \frac{1}{2\sqrt{x}} + \cos x\)
d. \( f'(x) = \sqrt{x}\cos x + \frac{1}{2\sqrt{x}} \sin x\)
e. \( f'(x) = \frac{1}{2\sqrt{x}} \cos x + \sqrt{x}\sin x\)
2. \(g(x) = \frac{2^x + 5}{x}\)
a. \( g'(x) = x 2^x - 1\)
b. \( g'(x) = \frac{x^2 2^{x-1}-2^x - 5}{x^2}\)
c. \( g'(x) = \frac{2^x + 5 - x2^{x-1}}{x^2}\)
d. \( g'(x) = (\ln 2)2^x\)
e. \( g'(x) = \frac{(\ln 2)x2^x - 2^x - 5}{x^2}\)
3. \(g(x) = x^e\)
a. \( g'(x) = (\ln x) x^e\)
b. \( g'(x) = e x^{e-1}\)
c. \( g'(x) = x^e\)
d. \( g'(x) = x^{e+1}\)
e. \( g'(x) = (\ln e) x^e\)
4. If \(f(x) = 2^x\), find \(f^{(10)}(x)\).
a. \(f^{(10)}(x)= (\ln 2)^{10} 2^x\)
b. \(f^{(10)}(x)= x 2^{x-1}\)
c. \(f^{(10)}(x)= (x)(x-1)\ldots(x-9) 2^{x-10}\)
d. \(f^{(10)}(x)= (x)(x-1)\ldots(x-10) 2^{x-10}\)
e. \(f^{(10)}(x)= (\ln 2)^{9} 2^x\)
In Problems 5 - 8 assume that the height, \(h\), of a hot-air balloon in meters, \(t\) minutes after it is launched is given by the function \( h(t) = t^3 - 8t^2 + 16 t\)
5. What is the height of the balloon after 2 minutes?
a. 2 m
b. 4 m
c. 8 m
d. 16 m
e. 32 m
6. What is the average vertical velocity of the balloon for the first two minutes of flight?
a. 2 m/minute
b. 4 m/minute
c. 8 m/minute
d. 16 m/minute
e. 32 m/minute
7. What is the vertical velocity of the balloon two minutes after launch?
b. -2 m/minute
c. -4 m/minute
d. 8 m/minute
e. -8 m/minute
8. What is the vertical acceleration of the balloon one minute after launch?
a. -10 m/minute2
b. 10 m/minute2
c. -12 m/minute2
d. -12 m/minute2
e. 22 m/minute2