Question

On a unit circle, the vertical distance from the x-axis to a point on the perimeter of the circle is twice the horizontal

Answer 1

Answer:

  (2/5)√5 ≈ 0.894427

Step-by-step explanation:

You require the y-coordinate of the point that satisfies two equations:

  x^2 +y^2 = 1

  y = 2x

Substituting for x, we have ...

  (y/2)^2 +y^2 = 1

  y^2(5/4) = 1

  y^2 = 4/5

  y = (2/5)√5 ≈ 0.894427

The sine of the angle is (2/5)√5 ≈ 0.894427.