Find the exact value of the expression.
-sec (-1215°)
A) $- 1$
B) $\frac { \sqrt { 2 } } { 2 }$
C) $- \frac { \sqrt { 3 } } { 3 }$
D) $- \sqrt { 2 }$

Name: Find the exact value of the expression. -sec (-1215°) A) $- 1$ B) $\frac { \sqrt { 2 } } { 2 }$ C) $- \frac { \sqrt { 3 } } { 3 }$ D) $- \sqrt { 2 }$
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Question

Find the exact value of the expression.
-sec (-1215°) 
A) $- 1$
B) $\frac { \sqrt { 2 } } { 2 }$
C) $- \frac { \sqrt { 3 } } { 3 }$
D) $- \sqrt { 2 }$

Quizplus · Accepted Answer

The angle -1215° is coterminal with -1215° + 3(360°) = -135°. The secant of -135° is the reciprocal of the cosine of -135°, which is -√2/2. Therefore, sec(-135°) = -1/(-√2/2) = -√2.

Find the Exact Value of the Expression −1- 1−1 B) 22\frac { \sqrt { 2 } } { 2 }22​​

Find the Exact Value of the Expression $- 1$ B) $\frac { \sqrt { 2 } } { 2 }$