Question

simplifique a expressão senx + sen(π+x) - sen (π/2-x) + cos x

Answer 1

Aplicando a soma de arcos

senx + sen(π+x) - sen (π/2-x) + cosx

senx + senπcosx + senxcosπ - [senπ/2cosx-senxcosπ/2] + cos x

senx + senπcosx + senxcosπ - senπ/2cosx+senxcosπ/2 + cos x

senx + 0.cosx + senx(-1) - 1.cosx+senx.0 + cos x

senx + senx(-1) - 1.cosx+ cos x

senx - senx - cosx+ cos x

0+0 = 0