if sec theta +tan theta= m and sec theta - tan theta = n then prove that mn = 1

Question

please answer this question fast......

Answer 1

First thing is you must familiar with those trigo identity. For this question,the identity that apply is tan ^2(theta)+1=sec ^2(theta) Substitute M and N, U will get sec ^2(theta)-tan^2(theta ) which equal to 1which according to that identity.

Answer 2

Multiplying the given equation.... We get sec^2theta -sectheta.tantheta+ tantheta.sectheta -tan^2theta=mn We got Sec ^2theta+ tan^2theta which is =1; So it is proved that mn =1;