Question

If Sin (A + B) = 1 and cos (A – B) = 1, 0° < A + B ≤ 90° A ≥ B. Find A & B

Answer 1

Sin(A + B) = 1

∴ Sin (A + B) = Sin 90°

A + B = 90° …(i)

Cos (A – B) = 1

Cos (A – B) = cos 0°

A – B = 0° …(ii)

Adding (i) and (ii) we get

A + B = 90°

`(A - B = 0^@)/(A = 90^@)`      `A = 45^@`

A – B = 0

A = B => B = 45°