Use double angle identity:
After substituting and moving to Right side of equation:
This is a quadratic, which can be solved by factoring or quadratic formula.
It may be helpful to replace sin(x) with another variable, then solve.
Now substitute sin(x) back in, we have
Using a unit circle or inverse sine function in calculator we can find the appropriate angles.
I did it out on paper if you needed to show work. But y is -1 and x is 1
Answer:
its second one all the best