document.write( "Question 984820: Can you help me please ;Given; sin (x+y) = sin x cos y + cos x sin y and cos (× + y)= cos x cos y - sin x sin y. If sin x = 0,8 and sin y= 0,6 , calculate sin ( x + y ) \n" ); document.write( "
Algebra.Com's Answer #605652 by solver91311(24713)\"\" \"About 
You can put this solution on YOUR website!

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document.write( "First, even though  and  are given, we still need to know  and  in order to calculate \r\n" );
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document.write( "If we know that , then we can determine the value of cosine by the following process:\r\n" );
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document.write( "Given:                  \r\n" );
document.write( "Square both sides:      \r\n" );
document.write( "Apply the Pythagorean\r\n" );
document.write( "  Identity              \r\n" );
document.write( "A little algebra        \r\n" );
document.write( "Take the root           \r\n" );
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document.write( "Since your problem does not restrict the value of  or  to a specific quadrant, the value of cosine, when calculated on the basis of the value of sine, is ambiguous.  We should look out for more than one solution to your problem.\r\n" );
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document.write( "Now we have all the information required to perform the needed calculation.\r\n" );
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document.write( "So\r\n" );
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document.write( "or\r\n" );
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document.write( "Hence\r\n" );
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document.write( "or\r\n" );
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\n" ); document.write( "John
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\n" ); document.write( "My calculator said it, I believe it, that settles it
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