document.write( "Question 1203962: If $\"+cos%28beta%29+=+-3+%2F+5+\"$ then, without a calculator, find $\"cos%28pi+%2F+2+-+beta%29+\"$ . Write your answer as a fraction. \n" ); document.write( "

Algebra.Com's Answer #839909 by ikleyn(52890) $\"\"$ $\"About$

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\n" ); document.write( "If $\"+cos%28beta%29+=+-3+%2F+5+\"$ then, without a calculator, find $\"cos%28pi+%2F+2+-+beta%29+\"$ .
\n" ); document.write( "Write your answer as a fraction.
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document.write( " =  =  =  = +/-  = \r\n" );
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document.write( "= +/-  = +/-  = +/-  = +/- .\r\n" );
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document.write( "Thus, there are two solutions and two answers are possible, 4/5 or -4/5, \r\n" );
document.write( "depending on to which quadrant the angle  does belong.\r\n" );
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document.write( "ANSWER.  If  is in QII, then   = 4/5.\r\n" );
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document.write( "         If  is in QIII, then   = -4/5.\r\n" );
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