Trigonometry Quiz

• 2

• 5

• 3

• 1

Work out the values of x between 0° and 360° for which 25 cos² x = 9. Give your answers to 1 decimal place.

• x = 53.13, 126.87, 233.13, 306.87

• x = 45.0°, 315.0°

• x = 60.0°, 300.0°

• x=45.28∘,118.92∘,214.56∘,299.81∘

Solve 3 sin 2x = 1 - sin 2x for 0 ≤ x < 360°.

• x = 30°, 150°, 210°, 330°

• x = 225°, 315°

• x=7, 82

• x = 90°, 180°

Solve 3 cos² θ + 5 cos θ - 2 = 0 for 0° < θ < 360°.

• θ = 60°, 300°

• θ = 23°, 337°

• θ = 70.5, 289.5

• θ = 81°, 109°

Find all the values of x, in the interval 0 ≤ x < 360°, for which 9 cos² x - 11 cos x + 3 sin² x = 0. Give your answers to 1 decimal place.

• x = 0°, 180°

• x = 70.5, 289.5

• x=45.12∘,312.87∘

• x=88.45∘,271.55∘

Tan 2x = 5 sin 2x can be written in the form (1 - 5 cos 2x) sin 2x = 0. Hence solve for 0 ≤ x ≤ 180°, giving your answers to 1 decimal place.

• x=15.78∘,134.92∘,249.37∘

• x=27.45∘,123.89∘,275.32∘

• x=42.17∘,98.64∘,167.29∘

• x = 90.0°, 36.9°, 140.77°