Question

simplifique a expressão y= sen(3π/2-x)-sen(π/2-x)/cos(π/2-x).cos(3π/2-x)

Answer 1

y=sen(3π/2-x)-sen(π/2-x)/cos(π/2-x).cos(3π/2-x)
y=(sen3π/2-senx-senπ/2+senx)/cos(π/2-x).cos(3π/2-x)
y=-1/cos(0-x).cos(-1-x)=
1/cos(-x).cos(x+1)