Question

5. (10.01 MC) If sin θ = 1 over 4 and tan θ > 0, what is the value of cos θ? (1 point)

Answer 1

From the trigonometry we should know that

sin² θ + cos² θ = 1

∴ cos² θ = 1 - sin² θ

given that ⇒⇒⇒ sin θ = 1/4

∴ cos² θ = 1 - sin² θ = 1 - (1/4)² = 0.9375

∴ cos θ = √0.9375 = 0.968 or -0.968
but sin θ is positive and tan θ positive because tan θ > 0 as stated in the problem
So, cos θ should be positive

∴ cos θ = 0.968