If cosecx – sinx = a3, secx – cosx = b3, then prove that a2 b2 (a2 + b2) = 1.

Given cosecx – sinx = a3


We know that cosecx = 1/ sinx.




We know that 1 – sin2x = cos2x


… (1)


Also given secx – cosx = b3


We know that secx = 1/ cosx




We know that 1 – cos2x = sin2x


… (2)


Consider LHS = a2b2 (a2 + b2)






We know that cos2 + sin2x = 1


= 1


= RHS


Hence proved.


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