Question

if sin theta - cos theta = sin 90. find sin4 theta + cos4theta .

Answer 1

it is also = sin90.......

sin90-cos90= 1-0 =1= =sin90
so
theta = 90

sin4theta+ cos4theta
= sin(4*90)+cos(4*90)
= sin360 +cos360
= 0+1= 1

so
1 = sin90. or cos0

Answer 2

I m not sure .....sry