I have no idea how to even begin this question.
Thank you!
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Answer:
Step-by-step explanation:
Start by solving for sin(x).
4sin(x)² = 2
sin(x)² = 1/2 . . . . divide by 4
sin(x) = ±√(1/2) = ±(√2)/2
Use your knowledge of the sine function to recognize that the reference angle is 45°, and that the angles x will be ...
x = ±45° or 180°±45° with multiples of 360° added
The solutions in the desired range are ...
x ∈ {135°, 225°, 315°, 405°}