- #1
chwala
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Homework Statement
[/B]
Solve ##2sin3x.sinx=1##
Homework Equations
The Attempt at a Solution
I used the identity ##( cos (A+B)= cos A cos B- sin A sin B),
(cos(A-B) = cos A cos B+sinA sinB)→
-(cos 4x-cos2x)= 2sin 3xsinx, (cos 2x-cos4x=1)##now i am stuck , is this correct_
using ##(cos 2x=2cos^2x-1)⇒(cos 4x=2cos^22x-1),→(2cos^22x-2cos^2x+1=0)##
is this correct, how do i move folks