Question

express root of 1-sina/1+sina as seca-tana

Answer 1

LHS=under root 1-sin titha/1+sin titha

multiply by (1-sin titha) to both numerator and denominator.

= under root (1-sin titha)×(1-sin titha) / (1+sin titha)×(1-sin titha)

= under root (1-sin titha)^2 /(1^2-sin^2 titha)

=(1- sin titha) / root cos^2 titha

=1-sin titha/cos titha

=1/cos titha -sin titha/cos titha

LHS=sec titha-tan titha

therefore LHS=RHS