Question

Please answer ASAP! If 0 is an angle in quadrant II, what is the value of sin(0)

Answer 1

Answer:

Option A

Step-by-step explanation:

It's given that cosθ = $-\frac{2\sqrt{5} }{5}$

Since, cosθ = $\frac{\text{Adjacent side}}{\text{Hypotenuse}}$ = $-\frac{2\sqrt{5} }{5}$

                                        = $\frac{2}{\sqrt{5}}$

By applying Pythagoras theorem in the right triangle,

(Hypotenuse)² = (Opposite side)² + (Adjacent side)²

(√5)² = (Opposite side)² + (2)²

5 = (Opposite side)² + 4  

Opposite side = √(5 - 4)

                       = 1

Since, sinθ = $\frac{\text{Opposite side}}{\text{Hypotenuse}}$

                  = $\frac{1}{\sqrt{5}}$

Since, sine is positive in IInd quadrant,

sinθ = $\frac{1}{\sqrt{5}}$

Therefore, option A will be the answer.