$\text { Evaluate the expression arccos } \left( \frac { \sqrt { 2 } } { 2 } \right) \text { without using a calculator. }$
A) $\frac { 5 \pi } { 4 }$
B) $\frac { \pi } { 6 }$
C) $\frac { 3 \pi } { 2 }$
D) $\frac { \pi } { 4 }$
E) $\frac { 2 \pi } { 3 }$

Question

$\text { Evaluate the expression arccos } \left( \frac { \sqrt { 2 } } { 2 } \right) \text { without using a calculator. }$ 
A) $\frac { 5 \pi } { 4 }$
B) $\frac { \pi } { 6 }$
C) $\frac { 3 \pi } { 2 }$
D) $\frac { \pi } { 4 }$
E) $\frac { 2 \pi } { 3 }$

Quizplus · Accepted Answer

Since $\cos(\frac{\pi}{4}) = \frac{\sqrt{2}}{2}$, we have $\arccos(\frac{\sqrt{2}}{2}) = \frac{\pi}{4}$. Therefore, the answer is choice D.

Evaluate the expression arccos (22) without using a calculator. \text { Evaluate the expression arccos } \left( \frac { \sqrt { 2 } } { 2 } \right) \text { without using a calculator. } Evaluate the expression arccos (22​​) without using a calculator.

$\text { Evaluate the expression arccos } \left( \frac { \sqrt { 2 } } { 2 } \right) \text { without using a calculator. }$