Answer:
x = 135°, 225°
Explanation:
You want the solution to the equation 2cos(x) +√2 = 0 on the interval [0°, 360°).
Solution
Subtracting √2 and dividing by 2 gives ...
2cos(x) = -√2
cos(x) = -√2/2
x = arccos(-√2/2), or 360° -arccos(-√2/2)
x = 135° or 225°
__
Additional comment
The attached graph is of 2cos(x)+√2, with x in degrees. Its value is zero at 135° and 225°.
<95141404393>