Verify the identity algebraically

Question

csc^4 x-2 csc^2 x+1=cot^4x

Answer 1

csc^4 x-2 csc^2 x+1=cot^4x

(1/sin)^4

I'm lost. Need ( ).

Is the x a value or is it *?

Answer 2

csc^4x - 2csc^2x + 1 = 1/sin^4x - 2/sin^2x + 1 = (1 - 2sin^2x + sin^4x) / sin^4x = (1 - sin^2x)^2/ sin^4x

cot^4x = cos^4x/sin^4x = cos^2x * cos^2x / sin^4x = (1 - sin^2x)*(1-sin^2x)/sin^4x = (1 - sin^2x)^2/ sin^4x