Trigonometrymedium · Past Paper
If sin A = 1/sqrt(2), find cos(2A).
A1
B0
C1/2
D-1
✓ Correct Answer: B — 0
cos(2A) = 1 - 2 sin^2 A = 1 - 2(1/2) = 0.
Share this question
More from Trigonometry
- Which ratio is equivalent to sin θ / cos θ?
- A tower subtends an angle α at a point A and elevation of top of a flagstaff on it is β. If h is flagstaff height, tower height is:
- The expression (1 + tan^2(A))(1 - sin^2(A)) is equal to:
- What is the value of sec 60?
- In a triangle, if sin^2 A + sin^2 B + sin^2 C = 2, the triangle is: