# Verify the following equation: cos^2x=sin^2x+2cos^2x-1?

• Verify the following equation: cos^2x=sin^2x+2cos^2x-1?

I am trying to solve the following equation for x. The textbook's answer and my answer differ and I keep getting the same answer. Could someone please tell ...
Positive: 62 %
You can prove it by using pythagoras' theorem using the following equation: r^2=y^2+x^2. Then divide throughout by r^2. y^2/r^2 + x^2/y^2 = 1.
Positive: 59 %

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Use the above values and the identities below to obtain values of trigonometric functions of the following multiples of /10: 3 /10 = /2 - /5, 2 /5 = /2 ...
Positive: 62 %
See the explanation below. Use one of the identities: cos2x = cos^2x-sin^2x cos2x = 1-2sin^2x cos2x = 2cos^2x-1 Playing around with them on scratch paper ...
Positive: 57 %
... the right side should ... [\cos^2x + \sin^2x = 1\] Add cos^2x to both ... so I knew the numerators should be equal. I multiplied it out to make ...