help

You asked:
sin^1/2(x)(cos(x))-sin^5/2(x)(cos(x))=cos^3(x)(sin^1/2(x))

Here's the thing, do you know X?

sin^5/2(x) → sin^1/2(x)*sin^2(x)  so:

 

sin^1/2(x)(cos(x))-sin^5/2(x)(cos(x))  →  sin^1/2(x)*cos(x)*(1 - sin^2(x)) → sin^1/2(x)*cos(x)*cos^2(x) → sin^1/2(x)*cos^3(x)

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