Question

Cos D= -3/4. if the sine of the angle is positive, find the sine of the angle and determine the quadrant.
Can anyone tell me the steps. I need to learn this.

Answer 1

sin^2 D = 1 - cos^2 D
The sin is + and the cos is - in Quadrant 2

Answer 2

Is cos^2D= 9/16

Answer 3

yes, cosine squared of D is 9/16

Answer 4

Soo what is the squareroot of 7/16?

Answer 5

1/4 sqrt7