Question

sin4A-cos4A=2sinsquareA-1=1-2cossquareA=sinsquareA-cossquareA​

Answer 1

Step-by-step explanation:

See Below

Explanation:

LHS = sin^4x−cos^4x

=(sin^2x−cos^2x) (sin^2x+cos^2x)

=(sin^2x−cos^2x)⋅1

=(1−cos^2x)−cos^2x (sin^2x+cos^2x=1)

=1−2cos^2x

=RHS