How do you verify (1-sin)/(1+sin) = (sec-tan)^21sin1+sin=(sectan)2?

1 Answer
Oct 12, 2016

see below

Explanation:

(1-sinx)/(1+sinx) = (secx-tanx)^21sinx1+sinx=(secxtanx)2

Left Side : =(1-sinx)/(1+sinx) =1sinx1+sinx

=(1-sinx)/(1+sinx) * (1-sinx)/(1-sinx) =1sinx1+sinx1sinx1sinx

=(1-2sinx+sin^2x)/(1-sin^2x)=12sinx+sin2x1sin2x

=(1-2sinx+sin^2x)/cos^2x=12sinx+sin2xcos2x

=1/cos^2x-(2sinx)/cos^2x+sin^2x/cos^2x=1cos2x2sinxcos2x+sin2xcos2x

=1/cos^2x-2 * 1/cosx sinx/cosx+sin^2x/cos^2x=1cos2x21cosxsinxcosx+sin2xcos2x

=sec^2x-2secxtanx+tan^2x=sec2x2secxtanx+tan2x

=(secx-tanx)(secx-tanx)=(secxtanx)(secxtanx)

=(secx-tanx)^2=(secxtanx)2

:.= Right Side