document.write( "Question 967280: Solve the following equation given that 0° ≤ θ < 360° :
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Algebra.Com's Answer #591206 by ikleyn(52803) $\"\"$ $\"About$

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\n" ); document.write( "\n" ); document.write( " $\"sin%28theta%29\"$ . $\"cos%282%2Atheta%29\"$ - $\"cos%282%2Atheta%29\"$ = 0,\r
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\n" ); document.write( "\n" ); document.write( " $\"sin%28theta%29\"$ . $\"cos%282%2Atheta%29\"$ = $\"cos%282%2Atheta%29\"$ .\r
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\n" ); document.write( "\n" ); document.write( "Case 1. $\"cos%282%2Atheta%29\"$ = 0.\r
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\n" ); document.write( "\n" ); document.write( "           The equation is satisfied at this value of $\"cos%282%2Atheta%29\"$ .\r
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\n" ); document.write( "\n" ); document.write( "           Then $\"2%2Atheta\"$ = 90° or 270°. \r
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\n" ); document.write( "\n" ); document.write( "           Hence, $\"theta\"$ = 45° or 135°.\r
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\n" ); document.write( "\n" ); document.write( "Case 2. $\"cos%282%2Atheta%29\"$ is not 0.\r
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\n" ); document.write( "\n" ); document.write( "           Then you can divide both sides of the equation \r
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\n" ); document.write( "\n" ); document.write( "            $\"sin%28theta%29\"$ . $\"cos%282%2Atheta%29\"$ = $\"cos%282%2Atheta%29\"$ .\r
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\n" ); document.write( "\n" ); document.write( "           by $\"cos%282%2Atheta%29\"$ . You will get \r
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\n" ); document.write( "\n" ); document.write( "            $\"sin%28theta%29\"$ = 1.\r
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\n" ); document.write( "\n" ); document.write( "           The solution is $\"theta\"$ = 90°. It is the only solution under the given condition 0° <= $\"theta\"$ < 360°.\r
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\n" ); document.write( "\n" ); document.write( "Answer. $\"theta\"$ = 45°, 90° or 135°.\r
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