document.write( "Question 1178825: solve tan 2x + sec 2x = 6 over the interval [0, 2pi) \n" ); document.write( "
Algebra.Com's Answer #808257 by MathLover1(20849)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "solve \"tan+%282x%29+%2B+sec+%282x%29+=+6\" over the interval [0, 2pi)\r
\n" ); document.write( "\n" ); document.write( "\"sin+%282x%29%2Fcos%282x%29+%2B+1%2Fcos%282x%29+=+6\" \r
\n" ); document.write( "\n" ); document.write( "\"%28sin+%282x%29%2B+1%29%2Fcos%282x%29+=+6+\"\r
\n" ); document.write( "\n" ); document.write( "\"%28sin+%282x%29%2B+1%29=+6cos%282x%29\" ......square both sides\r
\n" ); document.write( "\n" ); document.write( "\"%28sin+%282x%29%2B+1%29%5E2=+%286cos%282x%29%29%5E2\"\r
\n" ); document.write( "\n" ); document.write( "\"sin%5E2+%282x%29%2B2sin+%282x%29%2B+1=+36cos%5E2%282x%29\"...............since \"cos%5E2%282x%29=1-sin%5E2%282x%29\", we have\r
\n" ); document.write( "\n" ); document.write( "\"sin%5E2+%282x%29%2B2sin+%282x%29%2B+1=+36%281-sin%5E2%282x%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"sin%5E2+%282x%29%2B2sin+%282x%29%2B+1=+36-36sin%5E2%282x%29\"\r
\n" ); document.write( "\n" ); document.write( "\"sin%5E2+%282x%29%2B36sin%5E2%282x%29%2B2sin+%282x%29=36-1\"\r
\n" ); document.write( "\n" ); document.write( "\"37sin%5E2%282x%29%2B2sin+%282x%29-35=0\".....use quadratic formula\r
\n" ); document.write( "\n" ); document.write( "\"sin+%282x%29=%28-2%2B-sqrt%282%5E2-4%2A37%28-35%29%29%29%2F%282%2A37%29\"\r
\n" ); document.write( "\n" ); document.write( "\"sin+%282x%29=%28-2%2B-sqrt%284%2B5180%29%29%2F74\"\r
\n" ); document.write( "\n" ); document.write( "\"sin+%282x%29=%28-2%2B-sqrt%285184%29%29%2F74\"\r
\n" ); document.write( "\n" ); document.write( "\"sin+%282x%29=%28-2%2B-72%29%2F74\"\r
\n" ); document.write( "\n" ); document.write( "solutions:\r
\n" ); document.write( "\n" ); document.write( "\"sin+%282x%29=%28-2%2B72%29%2F74=70%2F74=35%2F37\"\r
\n" ); document.write( "\n" ); document.write( "or\r
\n" ); document.write( "\n" ); document.write( "\"sin+%282x%29=%28-2-72%29%2F74=-74%2F74=-1\"\r
\n" ); document.write( "\n" ); document.write( "so,\r
\n" ); document.write( "\n" ); document.write( "\"2x=sin%5E-1+%28-1%29\"
\n" ); document.write( "\"2x=-pi%2F2+\"
\n" ); document.write( "\"x=-pi%2F4\" (result in radians)\r
\n" ); document.write( "\n" ); document.write( "sin is negative in Q III or IV\r
\n" ); document.write( "\n" ); document.write( "\"x=215.54\"° (degrees)\r
\n" ); document.write( "\n" ); document.write( "or\r
\n" ); document.write( "\n" ); document.write( "\"2x=sin%5E-1+%2835%2F37%29\"
\n" ); document.write( "\"2x=1.24049897\"
\n" ); document.write( "\"x=1.24049897%2F2\"
\n" ); document.write( "\"x=0.620249485\"(result in radians)\r
\n" ); document.write( "\n" ); document.write( "in degrees:\r
\n" ); document.write( "\n" ); document.write( "\"x=35.54\"° (degrees)\r
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