Solving Trigonometric Equations Algebraically

Solve for 0≤x≤2π

2cos²x + cosx = 0

• π/2, 3π/2

• 0, π,2π

• 2π/3, 4π/3

• π/3, 5π/3

Solve for 0≤x≤2π

4cos²x - 2 = 0

• π/3, 5π/3

• π/4, 7π/4

• 3π/4, 5π/4

• π/6, 11π/6

Solve for 0≤x≤2π

sinxtanx = sinx

• π/2, 3π/2

• 3π/4, 7π/4

• 0, π, 2π

• π/4, 5π/4

Solve for 0≤x≤2π

2sin²x - 5sinx + 2 = 0

• π/6, 5π/6

• 7π/6, 11π/6

• π/3, 2π/3

• 4π/3, 5π/3

Solve for 0≤x≤2π

(cotx - √3) (cscx + 2)

• π/6

• 5π/6

• 7π/6

• 11π/6

Solve for 0≤x≤2π

2sin²x - sinx = 0

• 0, π, 2π

• π/2, 3π/2

• π/6, 5π/6

• π/3, 2π/3

Solve for 0≤x≤2π

3sin²x + sinx - 4 = 0

• 0, π

• π/2

• π/6, 5π/6

• 3π/2

Solve
cosθ = - √(3)/2  
on θ∈[0, 2π)

• θ = π /3, 2π /3
• θ = 2π /3, 4π /3
• θ = π /6, 5π /6
• θ = 5π /6, 7π /6

Which of the following is the solution of sin²x + cos²x = 2?

• 0

• π/4

• π/6

• no solution

Solve sinθ = -1 on θ∈[0, 2π)

• θ = π /2, 3π /2 
• θ = π /2
• θ = 3π /2
• θ = π