Question

Resolva a equação 2cosx=raiz de 2 no intervalo [0,2pi]
A) (45graus,135)
B) (45,225)
C)(135,225)
D)(45,315)
E)(45,135,225,315)

Answer 1

2cosx=√2

cosx = √2/2 ===> (+) 1°Q e 4°Q

x'= 45° (1°Q)

x"=360-45= 315° (4°Q)

==> D)(45,315) ✓