document.write( "Question 1160202: Find all solutions of the equation on the interval [0,2pi)\r
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Algebra.Com's Answer #783442 by ikleyn(52877) $\"\"$ $\"About$

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document.write( "-4sin(x) = -cos^2(x) + 4\r\n" );
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document.write( "Replace  cos^2(x)  by  1 - sin^2(x).  You will get\r\n" );
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document.write( "-4sin(x) = -(1-sin^2(x)) + 4\r\n" );
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document.write( "sin^2(x) + 4sin(x)x + 3 = 0\r\n" );
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document.write( "Factor\r\n" );
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document.write( "(sin(x) + 3)*(sin(x) + 1) = 0\r\n" );
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document.write( "The only real solution is  sin(x) = -1,  which gives  x = .    ANSWER\r\n" );
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document.write( "Plot y = -4sin(x) (red)  and  y = -cos^2(x) +4 (green)\r\n" );
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