Find all critical numbers for the function $f ( x ) = x - \cos x \text { for } 0

Question

Find all critical numbers for the function $f ( x ) = x - \cos x \text { for } 0 < x < 2 \pi$ .
A) $\frac { \pi } { 2 }$

B) $\frac { 3 \pi } { 2 }$ 
C)0
D)None of these
E) $\frac { \pi } { 3 }$ 
F) $\frac { \pi } { 4 }$

G)-1
H)No critical numbers

Quizplus · Accepted Answer

The Answer of Find all critical numbers for the function $f ( x ) = x - \cos x \text { for } 0 < x < 2 \pi$ .
A) $\frac { \pi } { 2 }$

B) $\frac { 3 \pi } { 2 }$ 
C)0
D)None of these
E) $\frac { \pi } { 3 }$ 
F) $\frac { \pi } { 4 }$

G)-1
H)No critical numbers

Find All Critical Numbers for the Function f(x)=x−cos⁡x for 0<x<2πf ( x ) = x - \cos x \text { for } 0 < x < 2 \pif(x)=x−cosx for 0<x<2π