Question

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

Answer 1

suppose i take theta=A
secA+tanA=m..............1
secA-tanA=n...............2
multiplying 1 and 2 we get
sec^2A - tan^2A= mn
1=mn (since sec^2A-tan^2A =1)
under root 1 = under root mn
1=under root mn. (since under root 1 =1)
hence proved