SOLUTION: Please help.
2 sin^2 theta + 5 cos theta = 4
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Question 426205: Please help.
2 sin^2 theta + 5 cos theta = 4
Answer by lwsshak3(11628) (Show Source): You can put this solution on YOUR website!
2 sin^2 theta + 5 cos theta = 4
..
let x=theta
2sin^2x+5cosx=4
2(1-cos^2x)+5cosx=4
2-2cos^2x+5cosx=4
2cos^x-5cosx+2=0
solve by factoring
(2cosx-1)(cosx-2)=0
2cosx-1=0
cosx=1/2
x=30 deg
..
cosx-2=0
cosx=2 (reject,cosx<=1)
..
ans:
Theta = 30 deg.
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