- #1

- 11

- 0

cos2x=cosx

I have to find all the values of x, and i know the answer is x=0°+120°, but i can figure ou how. I've tried it over and over and my answer turns out to x=0°=180°. Please help, thank you.:uhh:

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- Thread starter yeyspaz
- Start date

- #1

- 11

- 0

cos2x=cosx

I have to find all the values of x, and i know the answer is x=0°+120°, but i can figure ou how. I've tried it over and over and my answer turns out to x=0°=180°. Please help, thank you.:uhh:

- #2

Tide

Science Advisor

Homework Helper

- 3,089

- 0

HINT: [tex]\cos 2x = \cos^2 x - \sin^2 x[/tex]

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