document.write( "Question 1206408: Please help me with this equation.
\n" ); document.write( "An equation is given. (Enter your answers as a comma-separated list. Let k be any integer. Round terms to three decimal places where appropriate. If there is no solution, enter NO SOLUTION.)
\n" ); document.write( "1 − 2 sin(𝜃) = cos(2𝜃)
\n" ); document.write( "Find the solutions in the interval [0, 2𝜋).
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Algebra.Com's Answer #843854 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"1+-2+sin%28theta%29+=+cos%282theta%29\"\r
\n" ); document.write( "\n" ); document.write( "Find the solutions in the interval [\"0\", \"2pi\").\r
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\n" ); document.write( "\n" ); document.write( "\"1+-2+sin%28theta%29+=+cos%282theta%29\"....use identity \"cos%282theta%29=cos%5E2%28theta%29+-+sin%5E2%28theta%29\"\r
\n" ); document.write( "\n" ); document.write( "\"1+-2+sin%28theta%29+=+cos%5E2%28theta%29+-+sin%5E2%28theta%29\"\r
\n" ); document.write( "\n" ); document.write( "\"sin%5E2%28theta%29-cos%5E2%28theta%29+-2+sin%28theta%29+%2B1=+0\"...use identity \"cos%5E2%28theta%29=1-sin%5E2%28theta%29\"\r
\n" ); document.write( "\n" ); document.write( "\"sin%5E2%28theta%29-%281-sin%5E2%28theta%29%29+-2+sin%28theta%29+%2B1=+0\"\r
\n" ); document.write( "\n" ); document.write( "\"sin%5E2%28theta%29-1%2Bsin%5E2%28theta%29+-2+sin%28theta%29+%2B1=+0\"\r
\n" ); document.write( "\n" ); document.write( "\"2sin%5E2%28theta%29+-2+sin%28theta%29+=+0\"...factor\r
\n" ); document.write( "\n" ); document.write( "\"2sin%28theta%29%28sin%28theta%29+-1%29++=+0\"\r
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\n" ); document.write( "\n" ); document.write( "solutions:\r
\n" ); document.write( "\n" ); document.write( "if \"2sin%28theta%29+=+0\" =>\"sin%28theta%29+=+0\"
\n" ); document.write( "if \"2sin%28theta%29-1+=+0\" =>\"sin%28theta%29+=+1%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "find \"theta\"\r
\n" ); document.write( "\n" ); document.write( "\"theta=sin%5E-1%280%29\"=> \"theta=0\" (result in radians) or \"theta=0\"°
\n" ); document.write( "\"theta=sin%5E-1%281%2F2%29\"=>\"theta=+pi%2F6\" (result in radians) or\"theta=30\"°\r
\n" ); document.write( "\n" ); document.write( "the solutions in the interval [\"0\", \"2pi\")
\n" ); document.write( "\"theta=0\"or \"theta=0\"°
\n" ); document.write( "\"theta=pi%2F6\" or\"theta=30\"°
\n" ); document.write( "\"theta=5pi%2F6\" or\"theta=150\"°
\n" ); document.write( "\"theta=pi\" or\"theta=180\"°\r
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