Question

What is the value of sin(7pi/4)? See attached.

Answer 1

-sqrt(2)/2

Explanation:

did the test

Answer 2

-sqrt(2)/2 , the last option of your document.

Explanation:

sin(7pi/4) = -sin(7pi/4 - pi)

= -sin(7pi/4 - 4pi/4)

= - sin(3pi/4)

sin(3pi/4) is a special angle , which is sqrt(2)/2

Hence, sin(7pi/4) = -sin(3pi/4)

= -sqrt(2)/2