How do you simplify csc^2(-x)cos^2x(pi/2-x)csc2(x)cos2x(π2x)?

1 Answer
Nov 28, 2016

Express both factors in terms of sinxsinx

Explanation:

cscx=1/sinxcscx=1sinx

cos(pi/2-x) = sinxcos(π2x)=sinx

and sin(-x) =-sinxsin(x)=sinx

So:

csc^2(-x) cos^2(pi/2-x) = 1/sin^2(-x)sin^2(x) =1/(-sinx)^2sin^2(x)=1csc2(x)cos2(π2x)=1sin2(x)sin2(x)=1(sinx)2sin2(x)=1

Strictly speaking this is only true for x!=kpixkπ where the original expression is not defined.