Question

If sin^2(x) - 2sin(x) = 2, then sin(x) = _____.

Answer 1

Let z = sin(x).
.. z^2 -2z = 2
.. z^2 -2z +1 = 3
.. (z -1)² = 3
.. z -1 = ±√3
.. z = 1 -√3 . . . . . the positive solution is extraneous

sin(x) = 1 -√3