More trigonometric equations!!!

Hi, are the following lines of working correct?

Solve the following equations for 0 degrees <= x <= 360 degrees.
Example 1. (A student is supposed to copy down the working as the
teacher writes it up on the board, but since I'm self-learning I don't
have a teacher who has the teacher booklet with all the working in it
to copy from - questions done by oneself are under the Class
Exercises, not Examples).
(a) cos(x) + 2sin(x) = 0
cos(x) = -2sin(x)
cos(x) / sin(x) = -2sin(x) / sin(x)
cot(x) = -2
1 / tan(x) = -2 / 1
tan(x) = -1 / 2
x = atan(-1 / 2)
x approx. = 333 degrees 26 minutes, 153 degrees, 26 minutes

Example 2.
(a) sin^2(x) - sin(x) = 0
sin(x)[sin(x) - 1] = 0
sin(x) = 0 or sin(x) = 1
x = 0 degrees, 360 degrees, 180 degrees, 90 degrees

Could you please help me do Example 1. (b)?
[2sin(x) + 1)] [tan(x) + 1] = 0
I expanded the brackets, substituted tan(x) with sin(x) / cos(x) and
put most result over cos(x), and then I have + sin^2(x) + cos^2(x)

TIA
Albert
.

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