Q48 of 268 Page 5

If secθ – tanθ = x, then prove that

(i)


(ii)

(i) Given sec θ – tan θ = x

Taking RHS


Putting the value of x, we get




[∵ 1+ tan2 θ = sec2 θ]




= cos θ


=RHS


Hence Proved


(ii) Given sec θ – tan θ = x


Taking RHS


Putting the value of x, we get




[∵ 1+ tan2 θ = sec2 θ]




= sin θ


=RHS


Hence Proved


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