document.write( "Question 426205: Please help.\r
\n" ); document.write( "\n" ); document.write( "2 sin^2 theta + 5 cos theta = 4 \n" ); document.write( "
Algebra.Com's Answer #296808 by lwsshak3(11628)\"\" \"About 
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2 sin^2 theta + 5 cos theta = 4
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\n" ); document.write( "let x=theta
\n" ); document.write( "2sin^2x+5cosx=4
\n" ); document.write( "2(1-cos^2x)+5cosx=4
\n" ); document.write( "2-2cos^2x+5cosx=4
\n" ); document.write( "2cos^x-5cosx+2=0
\n" ); document.write( "solve by factoring
\n" ); document.write( "(2cosx-1)(cosx-2)=0
\n" ); document.write( "2cosx-1=0
\n" ); document.write( "cosx=1/2
\n" ); document.write( "x=30 deg
\n" ); document.write( "..
\n" ); document.write( "cosx-2=0
\n" ); document.write( "cosx=2 (reject,cosx<=1)
\n" ); document.write( "..
\n" ); document.write( "ans:
\n" ); document.write( "Theta = 30 deg.\r
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