document.write( "Question 772232: Find all the solutions to the equations in the interval (0, 2pi.
\n" ); document.write( "1. 2sin^2x=2+cosx
\n" ); document.write( "2. 2sin^2x+3sinx+1=0
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Algebra.Com's Answer #470784 by lwsshak3(11628)\"\" \"About 
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Find all the solutions to the equations in the interval (0, 2pi.
\n" ); document.write( "***
\n" ); document.write( "1. 2sin^2x=2+cosx
\n" ); document.write( "2(1-cos^2x)=2+cosx
\n" ); document.write( "2-2cos^2x=2+cosx
\n" ); document.write( "2cos^2x+cosx=0
\n" ); document.write( "cosx(2cosx+1)=0
\n" ); document.write( "..
\n" ); document.write( "cosx=0
\n" ); document.write( "no solution: (0 not in given domain)
\n" ); document.write( "..
\n" ); document.write( "2cosx+1=0
\n" ); document.write( "cosx=-1/2
\n" ); document.write( "x=2pi/3, 5pi/3
\n" ); document.write( "..
\n" ); document.write( "2. 2sin^2x+3sinx+1=0
\n" ); document.write( "solve for sinx using quadratic formula
\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
\n" ); document.write( "a=2, b=3, c=1
\n" ); document.write( "ans:
\n" ); document.write( "sinx=-1
\n" ); document.write( "x=3pi/2
\n" ); document.write( "or
\n" ); document.write( "sinx=-1/2
\n" ); document.write( "x=7pi/6, 11pi/6\r
\n" ); document.write( "\n" ); document.write( "solutions:x=2pi/3, 5pi/3, 3pi/2, 7pi/6, 11pi/6
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