Question

FIND THE VALUE OF COS -180 DEGREES. math help

Answer 1

Soluion:

`\cos(-180^o)`

Apply the reference angle by finding the agle with equivalent trig onometry values in the first quadrant. The expression woud be negative because the angle i in the second quarany at and cosine is negative in the second quadrant.

`\begin{gathered} \cos(-180^o)=-\cos(0) \\ \\ \cos(180^o)=-1 \end{gathered}`

ANSWER: -1