Krishna
0

Step 1: Identify the known parts of the problem.

NOTE:   \sin A = \cos B

Prove:  A  + B  = 90\degree

Step 2:  Make a use of the trigonometric ratios of complimentary angles.

NOTE:  We know \cos B = \sin (90\degree - B)............(1)

Step 3:  Prove the required equation

EXAMPLE: \sin A = \cos B

\sin A = \sin (90\degree - B) [ \because Equation (1)]

Cancel the \sin on both sides

A = 90\degree - B

A + = 90\degree