document.write( "Question 1207441: sin5A/sinA+cos5A/cosA=a+bcos4A \n" ); document.write( "

Algebra.Com's Answer #845328 by Edwin McCravy(20063) $\"\"$ $\"About$

You can put this solution on YOUR website!

\r\n" );
document.write( "Your problem should have been stated:\r\n" );
document.write( "Given\r\n" );
document.write( ",\r\n" );
document.write( "Determine the values of a and b.\r\n" );
document.write( "\r\n" );
document.write( "We look up the formulas for sin(5A), cos(5A), and cos(4A)\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( " \r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "We change the sines in the first two terms to cosines.  To change the first\r\n" );
document.write( "term:\r\n" );
document.write( "\r\n" );
document.write( " \r\n" );
document.write( "\r\n" );
document.write( "To change the second term\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "Substituting:\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "Simplifying:\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "This will be an identity if and only if the numerical coefficients on the left\r\n" );
document.write( "are equal to the literal coefficients of corresponding like terms on the right.\r\n" );
document.write( "\r\n" );
document.write( " \r\n" );
document.write( "\r\n" );
document.write( "Either of the first two equations give b=4, substituting in the third\r\n" );
document.write( "6=a+4 or a=2.\r\n" );
document.write( "\r\n" );
document.write( "Answer: a=2, b=4\r\n" );
document.write( "\r\n" );
document.write( "Edwin

\n" ); document.write( "

\n" );