Question

In a right triangle ABC, C is the right angle. What does cos A equal

1: cos(B)
2: both A and C
3: Cos(90-A)
4: sin(90-A)​

Answer 1

4

Explanation:

A+B+C = 180

C = 90

A+B = 90

A=90-B

Cos (A) = Sin(90-A)