Question

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

Answer 1

Option A

Explanation:

It's given that cosθ =
`-(2√(5) )/(5)`

Since, cosθ =
`\frac{\text{Adjacent side}}{\text{Hypotenuse}}` =
`-(2√(5) )/(5)`

=
`(2)/(√(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}}`

=
`(1)/(√(5))`

Since, sine is positive in IInd quadrant,

sinθ =
`(1)/(√(5))`

Therefore, option A will be the answer.