This equation cos2theta = 1, the closest equation using cos2theta double angle formula is the cos^2x - sin^2x version. But it is not exact. Can anyone show me the steps on how to complete the equation? The answer of 0 = 2y^2 is the nearest to y = 0 that I can solve without completing using dividing ...
"Throw yo' hands up!?" Attach yourself to this aspect of the equation if I did not mention it: The problem is asking to convert from polar to rectangular. Looking over my question I see I did not mention this part.
The only thing I need some instruction for this problem of cos2theta = 1 using polar to rectangular form. The result shown in the book is y = 0 but without any methods just the answer is useless. Thank you for your sympathies