Question

Sin (3pi/4) =_____ please help!!!

Answer 1

Answer:

That is asking you to find the sine of (3/4) PI radians.

If you look at the attached graphic, you will see that (3/4) PI radians = 135 degrees

Going to this calculator, we see that the sine of 135 degrees is 0.70711

https://www.1728.org/trigcalc.htm

Step-by-step explanation:

Answer 2

$sin\frac{3}{4}\pi=sin(\pi-\frac{\pi}{4})=sin\frac{\pi}{4}=\frac{\sqrt2}{2}$