document.write( "Question 1139293: I need help finding the exact values\r
\n" ); document.write( "\n" ); document.write( "Use a double-angle identity to find the exact value of each expression.\r
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\n" ); document.write( "\n" ); document.write( "1. sin 120°\r
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\n" ); document.write( "\n" ); document.write( "2. tan 60°\r
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\n" ); document.write( "\n" ); document.write( "3. cos 4π/3\r
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\n" ); document.write( "\n" ); document.write( "4. sin 5π/3''.
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Algebra.Com's Answer #757086 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "Use a double-angle identity to find the exact value of each expression. \r
\n" ); document.write( "\n" ); document.write( "1.
\n" ); document.write( " \"sin%28+120+%29\"..........use identity \"sin%28+2a%29+=+2sin%28a%29+cos%28a%29\"\r
\n" ); document.write( "\n" ); document.write( "=\"sin%28+2%2A60%29\"\r
\n" ); document.write( "\n" ); document.write( "=\"2sin%2860%29+cos%2860%29\"\r
\n" ); document.write( "\n" ); document.write( "=\"2sqrt%283%29%2F2%2A%281%2F2%29\"\r
\n" ); document.write( "\n" ); document.write( "=\"cross%282%29sqrt%283%29%2F2%2A%281%2Fcross%282%29%29\"\r
\n" ); document.write( "\n" ); document.write( "=\"sqrt%283%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "2. \r
\n" ); document.write( "\n" ); document.write( "\"tan+%2860%29\"° \r
\n" ); document.write( "\n" ); document.write( "=\"tan+%282%2A30%29+\"\r
\n" ); document.write( "\n" ); document.write( "=\"sin+%282%2A30%29+%2Fcos%282%2A30%29\".........................\"sin%28+2a%29+=+2sin%28a%29+cos%28a%29\" and \"cos+%282a%29+=+cos%5E2%28a%29+-+sin%5E2%28a%29+\"\r
\n" ); document.write( "\n" ); document.write( "=\"%282sin%2830%29+cos%2830%29%29%2F%28cos%5E2%2830%29+-+sin%5E2%2830%29+%29\"\r
\n" ); document.write( "\n" ); document.write( "=\"%282%281%2F2%29+%28sqrt%283%29%2F2%29%29%2F%283%2F4+-+1%2F4+%29\"\r
\n" ); document.write( "\n" ); document.write( "=\"%281%2A+%28sqrt%283%29%2F2%29%29%2F%282%2F4+%29\"\r
\n" ); document.write( "\n" ); document.write( "=\"4sqrt%283%29%2F4\" \r
\n" ); document.write( "\n" ); document.write( "=\"sqrt%283%29\"\r
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\n" ); document.write( "\n" ); document.write( "3.\r
\n" ); document.write( "\n" ); document.write( "\"+cos+%284pi%2F3+%29\"\r
\n" ); document.write( "\n" ); document.write( "=\"cos+%282%2A%282pi%2F3+%29%29\"\r
\n" ); document.write( "\n" ); document.write( "= \"cos%5E2%282pi%2F3%29+-+sin%5E2%282pi%2F3%29+\"\r
\n" ); document.write( "\n" ); document.write( "=\"1%2F4-3%2F4\"\r
\n" ); document.write( "\n" ); document.write( "=\"-2%2F4\"\r
\n" ); document.write( "\n" ); document.write( "=\"-1%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "4. \r
\n" ); document.write( "\n" ); document.write( "\"sin%28+5pi%2F3+%29\"\r
\n" ); document.write( "\n" ); document.write( "=\"sin%28+3pi%2F3+%2B2pi%2F3%29\"\r
\n" ); document.write( "\n" ); document.write( "=\"sin%28+pi+%2B2pi%2F3%29\"..........use \"sin+%28a+%2B+b%29+=+sin+%28a%29+cos%28+b%29+%2B+sin+%28b%29+cos+%28a%29\"\r
\n" ); document.write( "\n" ); document.write( "=\"sin%28+pi%29cos%282pi%2F3%29+%2Bsin%282pi%2F3%29cos%28pi%29\"\r
\n" ); document.write( "\n" ); document.write( "=\"0%2A%28-1%2F2%29+%2B%28sqrt%283%29%2F2%29%28-1%29\"\r
\n" ); document.write( "\n" ); document.write( "=\"-sqrt%283%29%2F2\"\r
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