Question

If sinA-cosA=0 then the value of sin^4A-cos^4A

Answer 1

Answer:

$\sin {}^{4} ( \alpha ) - \cos {}^{4} ( \alpha ) =( \sin {}^{2} \alpha + \cos {}^{2} \alpha )(\sin {}^{2} \alpha - \cos {}^{2} \alpha ) = 1 \times (\sin \alpha + \cos \alpha )(\sin \alpha - \cos \alpha ) = 1 \times (\sin \alpha + \cos \alpha ) \times 0 = 0$