Find All Solutions in the Interval [0, 2π]
- $$\cos ^ { 2 } x + 2 \cos x + 1 = 0$$

question 237

Multiple Choice

Find all solutions in the interval [0, 2π]
- $$\cos ^ { 2 } x + 2 \cos x + 1 = 0$$

• A) \(x = \frac { \pi } { 2 } , \frac { 3 \pi } { 2 }\)
• B) \(x = 2 \pi\)
• C) \(x = \pi\)
• D) \(x = \frac { \pi } { 4 } , \frac { 7 \pi } { 4 }\)

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An ability to vividly recall images with high precision for a brief period after seeing them, often referred to as eidetic memory.

Eidetic Memories

The rare ability to recall images, sounds, or objects with extreme precision and detail, often referred to as photographic memory.

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Highly detailed, exceptionally vivid 'snapshot' of the moment and circumstances in which a piece of surprising and consequential news was heard.