Question

Fie x masura unui unghi ascutit, Aratati ca :
Sinx supra 1-cosx = 1+cosx supra sin

Answer 1

[tex]x\in (0,\frac{\pi}{2}),\frac{sinx}{1-cosx}=\frac{1+cosx}{sinx}\\ sin^2x=(1-cosx)(1+cosx)\\ sin^2x=1-cos^2x\\ sin^2x+cos^2x=1(A)[/tex]