[1]" "(1+sinx)/(1-sinx)-(1-sinx)/(1+sinx)[1] 1+sinx1−sinx−1−sinx1+sinx
Combine the two terms by making them have the same denominator.
[2]" "=((1+sinx)/(1-sinx))((1+sinx)/(1+sinx))-((1-sinx)/(1+sinx))((1-sinx)/(1-sinx))[2] =(1+sinx1−sinx)(1+sinx1+sinx)−(1−sinx1+sinx)(1−sinx1−sinx)
[3]" "=(1+2sinx+sin^2x)/(1-sin^2x)-(1-2sinx+sin^2x)/(1-sin^2x)[3] =1+2sinx+sin2x1−sin2x−1−2sinx+sin2x1−sin2x
[4]" "=(1+2sinx+sin^2x-1+2sinx-sin^2x)/(1-sin^2x)[4] =1+2sinx+sin2x−1+2sinx−sin2x1−sin2x
[5]" "=(4sinx)/(1-sin^2x)[5] =4sinx1−sin2x
Pythagorean Identity: 1-sin^2theta=cos^2theta1−sin2θ=cos2θ
[6]" "=(4sinx)/(cos^2x)[6] =4sinxcos2x
[7]" "=(4sinx)/((cosx)(cosx))[7] =4sinx(cosx)(cosx)
Quotient Identity: sintheta/costheta=tanthetasinθcosθ=tanθ
[8]" "=(4tanx)/(cosx)[8] =4tanxcosx
Reciprocal Identity: 1/costheta=sectheta1cosθ=secθ
[9]" "=4tanxsecx[9] =4tanxsecx
color(blue)("":.(1+sinx)/(1-sinx)-(1-sinx)/(1+sinx)=4tanxsecx)