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
- Simplify cos(60+A) + cos(60-A).
- The angle of depression of a boat from a bridge 25 m high is 30°. Find the horizontal distance of the boat from the bridge.
- If base = 8 and hypotenuse = 10, find cos theta.
- If a bird is 40 m high and the angle of elevation from a boy is 30°, how far is the bird from the boy's eye?
- Value of tan 0° is: