document.write( "Question 947169: cos(x+pi/2) = -sin(x) \n" ); document.write( "

Algebra.Com's Answer #577874 by MathLover1(20849) $\"\"$ $\"About$

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document.write( "cos(x+pi/2)=-sin (x)\r\n" );
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document.write( "cos(x + pi/2) = -sin (x)\r\n" );
document.write( "cos(pi/2 - (-x)) = -sin (x)\r\n" );
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\n" ); document.write( "\n" ); document.write( "Apply the co-function property:\r
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document.write( " [cos(pi/2 + x) = sin (x)]\r\n" );
document.write( "sin (-x) = -sin (x)\r\n" );
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\n" ); document.write( "\n" ); document.write( "Apply the even/odd formula:
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document.write( "[sin (-x) = - sin (x)]\r\n" );
document.write( "-sin (x) = - sin (x)\r\n" );
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