1. **State the problem:** Solve the trigonometric equation $$\cos x + \sqrt{2} = -\cos x$$ on the interval $$[0, 2\pi)$$.
2. **Rewrite the equation:** Move all terms involving $$\cos x$$ to one side:
$$\cos x + \sqrt{2} = -\cos x \implies \cos x + \cos x = -\sqrt{2}$$
3. **Combine like terms:**
$$2\cos x = -\sqrt{2}$$
4. **Isolate $$\cos x$$:**
$$\cos x = \frac{-\sqrt{2}}{2}$$
5. **Recall the cosine values:**
$$\cos x = -\frac{\sqrt{2}}{2}$$ corresponds to angles where cosine is negative and equals $$-\frac{\sqrt{2}}{2}$$.
6. **Find reference angle:**
The reference angle for $$\cos x = \frac{\sqrt{2}}{2}$$ is $$\frac{\pi}{4}$$.
7. **Determine solutions in $$[0, 2\pi)$$:**
Cosine is negative in the second and third quadrants, so:
$$x = \pi - \frac{\pi}{4} = \frac{3\pi}{4}$$
$$x = \pi + \frac{\pi}{4} = \frac{5\pi}{4}$$
8. **Write the final answer in increasing order:**
$$x = \frac{3\pi}{4}, \frac{5\pi}{4}$$
Solve Cosine E2C72D
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