Question

Como calcular passo a passo simplifique: sen(pi + x) + cos(pi-x)

Answer 1

Usando sen(a+b)=sena*cosb+senb*cosa e cos(a-b)=cosa*cosb+senb*sena

sen(pi+x)=senpi*cosx+senx*cospi=0*cosx+senx*(-1)=-senx ——> sen(pi+x)= -senx

cos(pi-x)= cospi*cosx+senx*senpi= (-1)*cosx+senx*0=-cosx ——> cos(pi-x)= -cosx