#### Unicornstodope

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Can’t figure this equation out, can someone help?

sin^2 (5x)=1

sin^2 (5x)=1

- Thread starter Unicornstodope
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Can’t figure this equation out, can someone help?

sin^2 (5x)=1

sin^2 (5x)=1

- Joined
- Aug 4, 2019

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Please help me solve this equation.

2cos^2 (4theta) +3cos(4theta) +1=0

2cos^2 (4theta) +3cos(4theta) +1=0

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What do you get if you take the square root of both sides?Can’t figure this equation out, can someone help?

sin^2 (5x)=1

Observe that you have a quadratic in \(\cos(4x)\)...can you proceed?Please help me solve this equation.

2cos^2 (4theta) +3cos(4theta) +1=0

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Yes

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\(\displaystyle \sin(5x)=\pm1\)

This implies:

\(\displaystyle 5x=\frac{\pi}{2}+k\pi=\frac{\pi}{2}(2k+1)\) where \(k\in\mathbb{Z}\)

Hence:

\(\displaystyle x=\frac{\pi}{10}(2k+1)\)

Does this make sense? What do you get when factoring the second equation?

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I got this one

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Just need the first one please

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The 1 first one is different I figured the second one

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I tried to parse your wording, above. (Your last post is not clear, regarding what you're working on now or what kind of help you need.)The [first] one is different[.] I figured the second one[.]

Please follow the forum guidelines (see the

In the future, please start a new thread for each new exercise. Cheers!

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