Question

P.t (sec a +tan a)^2=cosec a+1/cosec a -1

Answer 1

Lhs=(secA +tanA)^2 =sec^2A + tan^2A + 2secAtanA =1/cos^2A +sin^2A/cos^2A + 2sinA/cos^2A = 1+ sin^2A + 2sinA /cos^2A = (1+sinA)^2/1-sin^2A = (1+sinA)(1+sinA)/(1+sinA)(1-sinA) = 1+1/cosecA/1-1/cosecA = cosecA +1/cosecA × cosecA/cosecA-1 =cosecA +1 /cosecA -1 = Rhs