How do you solve 1/(cosx-sinx)=cosx+sinx1cosxsinx=cosx+sinx?

1 Answer
Dec 7, 2016

x = 0 + 2pin, pi + 2pin, cosx - sinx !=0x=0+2πn,π+2πn,cosxsinx0

Explanation:

Make the equation into a product.

1 = (cosx + sinx)(cosx - sinx)1=(cosx+sinx)(cosxsinx)

1 = cos^2x - sin^2x1=cos2xsin2x

Solve the pythagorean identity sin^2x + cos^2x = 1sin2x+cos2x=1 for cos^2xcos2x and substitute.

1 = 1- sin^2x - sin^2x1=1sin2xsin2x

0 = -2sin^2x0=2sin2x

0 = sinx0=sinx

x = 0 + 2pin, pi + 2pinx=0+2πn,π+2πn

Our restrictions are cosx- sinx != 0cosxsinx0.

Hopefully this helps!