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Narain
Nov 3, 2008, 12:59 AM
2cos2x=1-7sinx-2cos2x

basilrazi
Nov 3, 2008, 01:12 AM
I cannot get past this:

2cos2x+2cos2x=1-7sinx
4cos2x=

basilrazi
Nov 3, 2008, 01:13 AM
sorry pressed eneter

4cos2x=1-7sinx

ebaines
Nov 3, 2008, 10:29 AM
Recall that cos2x = 1 - 2 sin^2x. Now you have a quadratic and can solve for sinx.

Unknown008
Nov 4, 2008, 03:14 AM
And lastly for 'x'.