Question

evaluate sin (-225)

and sec 10pi/3

Answer 1

sin(-225)=sin(270-45)=sin(270)cos(45) - cos(270)sin(45)

sin(270) =-1
cos(270)= 0

sin(45) and cos(45) are both \(\LARGE\color{blue}{ \bf \frac{2}{\sqrt{2}} }\)

Answer 2

Let me know if you need more help.

Answer 3

yes I use help with the second one if possible