Mulitple Choice

Question

Find cos0 if sin0=3/5 and 90 degrees<0<180 degrees.
A.)4/5
B.)-4/5
C.)(Sq root 34)/5
D.)(- sq root 34)/5

Answer 1

sinA = 3/5 = Y/r,
X^2 + 3^2 = 5^2,
X^2 = 25 - 9 = 16,
X = +-4,
X = -4(Q2).

cosA = X/r = -4/5.