Solve the equation (x in radians and in degrees) for all exact solutions where appropriate. Round approximate answers
in radians to four decimal places and approximate answers in degrees to the nearest tenth.
-$\cos ^ { 2 } x - \cos x = 0$
A) $\left\{ \frac { 5 \pi } { 3 } + 2 n \pi \right\}$
B) $\left\{ \frac { \pi } { 2 } + 2 n \pi \right\}$
C) $\{ \pi + 2 n \pi \}$
D) $\left\{ 2 \mathrm { n } \pi , \frac { \pi } { 2 } + \mathrm { n } \pi \right\}$

Question

Quizplus · Accepted Answer

The equation $\cos^2x - \cos x = 0$ can be factored as $\cos x(\cos x - 1) = 0$, leading to $\cos x = 0$ or $\cos x = 1$. The solutions for $\cos x = 0$ are $x = \frac{\pi}{2} + n\pi$, and for $\cos x = 1$, the solution is $x = 2n\pi$, where $n$ is any integer.

Solve the Equation (X in Radians and in Degrees) for All