Q27 of 40 Page 422

Prove that

Taking LHS



Dividing by cosθ in numerator and denominator



Using and



Putting 1 = sec2θ - tan2θ in numerator




Using a2 - b2 = (a + b)(a - b)




= tan θ + sec θ


Now, taking RHS



Multiplying and dividing by secθ + tanθ = 1




= tanθ + secθ [As sec2θ - tan2θ = 1]


LHS = RHS


Hence Proved.


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