Question

Determine x, em radiano, sabendo que cos (x-π/2)=1

Answer 1

Sabemos que:

$\boxed{cos(a-b)=cosa*cosb+sena*senb}\\\\ cos(x-\frac{\pi}{2})=1\\\\ cosx*cos\frac{\pi}{2}+senx*sen\frac{\pi}{2}=1\\\\ cosx*0+senx*1=1\\\\ senx=1\\\\ x=0\ ou\ x=\pi\ ou\ x=2\pi\\\\ \boxed{S(0+k\pi),\ onde\ KEZ}$