SOLUTION: How proof this? 1)4* cos ^4 x + 4* sin ^2 -3 = cos ^2 2X 2) cos ^4

SOLUTION: How proof this? 1)4* cos ^4 x + 4* sin ^2 -3 = cos ^2 2X 2) cos ^4 - sin ^4X = cos 2X

Question 682713: How proof this?
1)4* cos ^4 x + 4* sin ^2 -3 = cos ^2 2X
2) cos ^4 - sin ^4X = cos 2X
Answer by solver91311(24713) (Show Source): You can put this solution on YOUR website!

You can't prove either one of those. x and X are two different things. In the first one you have a sine function with no argument. In the second one you have a cosine function with no argument.

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

The Out Campaign: Scarlet Letter of Atheism

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