Question

cos90=cos²45-sin²45​

Answer 1

LHS

cos 90=1

RHS

cos^2( 45) + sin^2(45)

1

so

LHS =RHS =1

Answer 2

Answer:

Given equation is incorrect

Step-by-step explanation:

cos90 = 1

cos²45 - sin²45

= (1/√2)² - (1/√2)²

= 0

1 ≠ 0