Question

(Write only the Final answer)
5 sin 8 +3 cos
25. If 4 cot 0 = 5 find the value of
5 sin 0-2 cos e
Your answer​

Answer 1

Step-by-step explanation:

Find these angles in degrees: (a) π/6; (b) 2π; (c) 1 (that’s right, radian angles aren’t necessarily fractions or multiples of π).

Solutions:

(a) (π/6) × (180°/π) = 30°

(b) 2π × (180°/π) = 360°

(c) 1 × (180°/π) = (180/π)° ≈ 57.3°

2 Which is the correct definition of an acute angle, in interval notation?

(a) (0°, 90°) (b) [0°, 90°]

Answer: (0°, 90°) is 0 to 90 degrees excluding 0° and 90°; [0°, 90°] is 0 to 90 degrees including 0° and 90°. Acute angles are between 0° and 90° exclusive, so the answer is (a) (0°, 90°).

3 Two angles of a triangle are 80° and 40°. Fine the third angle.

Solution: The inside angles of a triangle must always add to 180°. 80° + 40° = 120°, so to make the full 180° the third angle must be 60°.

4 A triangle has an angle of 90°. The two short sides (next to that angle) are 5 and 12. Find the third side.

Solution: Cue the Pythagorean Theorem!

c² = a² + b²

c² = 5² + 12²

c² = 25 + 144 = 169

c = √169 = 13

5 Find these angles in radian measure: (a) 60° (b) 126°; (c) 45°.

Where possible, give an exact answer rather than a decimal approximation.

Solutions:

(a) 60° + (π/180°) = π/3.

(b) 126° × (π/180°) ≈ 2.20

(c) 45° × (π/180°) = π/4

Notice that you don’t have to say “radians” when