UTMA Trigonometry 2 — Questions and Answers
Question 1: What is sin(90°)?
- 0
- 1/2
- √2/2
- 1 (Correct answer)
Correct answer: 1
At 90°, the point on the unit circle is (0,1), so sin(90°) = 1.
Question 2: Which angle has a cosine value of 0?
- 0°
- 45°
- 90° (Correct answer)
- 180°
Correct answer: 90°
cos(90°) = 0 because the unit circle point at 90° has x-coordinate 0.
Question 3: What is the period of y = sin(2x)?
- 4π
- 2π
- π (Correct answer)
- π/2
Correct answer: π
The period of sin(Bx) is 2π/B = 2π/2 = π.
Question 4: In triangle ABC, if angle A = 60°, side a = 6, and side b = 4, what law would you use to find angle B?
- Pythagorean theorem
- Law of Cosines
- Law of Sines (Correct answer)
- Sum of angles only
Correct answer: Law of Sines
The Law of Sines (a/sinA = b/sinB) is used when two sides and the opposite angle are known.
Question 5: What is cos(60°)?
- 1/2 (Correct answer)
- √3/2
- √2/2
- 1
Correct answer: 1/2
cos(60°) = 1/2 from the 30-60-90 triangle ratios.
Question 6: If sin(θ) = 5/13 and θ is in the first quadrant, what is cos(θ)?
- 12/13 (Correct answer)
- 5/12
- 13/12
- 8/13
Correct answer: 12/13
Using sin²θ + cos²θ = 1: cos²θ = 1 − 25/169 = 144/169, so cos θ = 12/13.
UTMA Trigonometry 2
What is sin(90°)?