Randolph College
Department of Mathematics and Computer Science

 

Homework # 2 - Math 1150


The problems on this homework must be done alone.  The honor code is in effect.

You may submit the solutions twice, if you wish.

 First Name:  Last Name:

 

1.  Find all extreme points of \(f(x) = \frac{\ln x}{x}\).

a.  Maximum at \(x = 1\), no minimum.

b.  Minimum at \(x = 1\), no maximum.

c.  Maximum at \(x = 1\), minimum at \(x = e\).

d.  Maximum at \(x = e\), no minimum.

e.  Maximum at \(x = 3\), minimum at \(x = 0\).

 

2.  Compute the indefinite integral  \( \int \frac{x+1}{x^2+2x+5} dx\).

a.  \( \ln(x^2+2x+5) + c\)

b.  \( \frac{1}{2}\ln(x^2+2x+5) + c\)

c.  \( \frac{(\frac{1}{2})x^2 + x}{(\frac{1}{3})x^3 + x^2 + 5x} + c\)

d.  \( (x+1)\ln(x^2+2x+5) + c\)

e.  \( \frac{-x^2 - 2x - 1}{(x^2 + 2x +5)^2} + c\)

 

3.  Compute the indefinite integral  \( \int \frac{1}{x\ln(x^3)} dx\).

a.  \( \frac{1}{3} \ln(\ln(x^3)) + c\)

b.  \( \frac{1}{2} \ln(\ln(x^3)) + c\)

c.  \( \ln(\ln(x^3)) + c\)

d.  \( \frac{3x^2}{\ln(x^3)} + c\)

e.  \( \frac{3x^2}{\ln(3x^2)} + c\)

 

4.  Compute the indefinite integral  \( \int \frac{x^4 + x^3 + 2x^2 + x + 1}{x^2 + 1} dx \).

a.  \( 2x + \ln (x^2 + 1) + c \)

b.  \( 2x + \frac{1}{2}\ln (x^2 + 1) + c \)

c.  \( 2x + \frac{1}{3}\ln (x^2 + 1) + c \)

d.  \( x^2 + x + 1 + c \)

e.  \( \frac{1}{3} x^3 + \frac{1}{2} x^2 + x + c\)

 

5.  If \( f(x) = (x - 1)^3\), find \(f^{-1}(x)\).

a.  \( f^{-1}(x) = \sqrt[3]{x-1} \)

b.  \( f^{-1}(x) = \sqrt[3]{x+1} \)

c.  \( f^{-1}(x) = \sqrt[3]{x}-1 \)

d.  \( f^{-1}(x) = \sqrt[3]{x}+1 \)

e.  \( f(x)\) has no inverse.