Can we write:
cos^2 (90-A)=sin^2 A
yes, we can write cos square (90-A) as sin square A. the solution of your query is given below with full derivation
we can also write it as, cos square (90-A) = cos (90-A). cos(90-A)
cos square (90-A) = sin A . sinA (because cos (90 -A) = sin A )
cos square (90-A) = sin square A = RHS
LHS = RHS
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we can also write it as, cos square (90-A) = cos (90-A). cos(90-A)
cos square (90-A) = sin A . sinA (because cos (90 -A) = sin A )
cos square (90-A) = sin square A = RHS
LHS = RHS
HENCE PROVED (HOPE LIKE MY SUGGESTION)
GIVE THUMBS UP TO MY SUGGESTION