How to prove?

(1+secx)/(tan^(2)x)=(cosx)/(1-cosx)

2 Answers
Mar 3, 2018

=L.H.S

=(1+secx)/(tan^2x)

=((1+1/cosx)/(sin^2x/cos^2x))

=(cosx+1)/cosx xxcos^2x/sin^2x

=((cosx+1)cosx)/sin^2x

=((cosx+1)cosx)/((1-cos^2x))

=(cancelcolor(blue)((cosx+1))cosx)/(cancelcolor(blue)((1+cosx))(1-cosx))

=cosx/(1-cosx)

=R.H.Scolor(green)([Proved.])

Mar 3, 2018

See below

Explanation:

(1+secx)/tan^2x=cosx/(1-cosx)

(1+secx)/(1-sec^2x)=cosx/(1-cosx)

(1+secx)/((1+secx)(1-secx))=cosx/(1-cosx)

1/(1-secx)=cosx/(1-cosx)

1/(cosx/cosx-1/cosx)=cosx/(1-cosx)

1/((cosx-1)/cosx)=cosx/(1-cosx)

cosx/(1-cosx)=cosx/(1-cosx)