Respuesta :

I used x instead of Ф.

[tex] sinx- (cos x)^{2} *sinx= (sin x)^{3} [/tex]

[tex]sinx(1-(cos x)^{2})=(sin x)^{3}[/tex]

You use the fundamental formula sin^2x+cos^2x=1

sinx*sin^2x=sin^3x
sin^3x=sin^3x