Q15 of 46 Page 1

Prove that:


OR


Prove that:



Taking LHS



We know that,


(a + b)(a – b) = (a2 – b2)



…(i)


We also know that,


1 + tan2θ = sec2θ


or 1 – sec2θ = -tan2θ


So, eq. (i) become







= 2 cosecA


= RHS


∴ LHS = RHS


Hence Proved


OR


Taking LHS








[∵sin2θ + cos2θ = 1]



= cosec θ


= RHS


∴ LHS = RHS


Hence Proved


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