document.write( "Question 1208309: 1/tan^2pie/8 - 1/sin^2pie/8\r
\n" ); document.write( "\n" ); document.write( "Evaluate\r
\n" ); document.write( "\n" ); document.write( "Thanks
\n" ); document.write( "

Algebra.Com's Answer #846648 by ikleyn(52879)\"\" \"About 
You can put this solution on YOUR website!
.
\n" ); document.write( "1/tan^2pie/8 - 1/sin^2pie/8
\n" ); document.write( "Evaluate
\n" ); document.write( "~~~~~~~~~~~~~~~~~\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "        I will evaluate an expression   \"1%2Ftan%5E2%28x%29\" - \"1%2Fsin%5E2%28x%29\"   for arbitrary  x =/= 0, +/-\"pi\", +/-\"2pi\", . . . \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "
\r\n" );
document.write( "We have  \"1%2Ftan%5E2%28x%29\"} = \"cos%5E2%28x%29%2Fsin%5E2%28x%29\".\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "THEREFORE,  \"1%2Ftan%5E2%28x%29\" - \"1%2Fsin%5E2%28x%29\" = \"cos%5E2%28x%29%2Fsin%5E2%28x%29\" - \"1%2Fsin%5E2%28x%29\" = \"%28cos%5E2%28x%29-1%29%2Fsin%5E2%28x%29\".\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "The numerator is  \"-sin%5E2%28x%29\", by Pythagoras.  THEREFORE, the last fraction in the previous line is -1.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "ANSWER.  The expression  \"1%2Ftan%5E2%28x%29\" - \"1%2Fsin%5E2%28x%29\"  is identically equal to -1 \r\n" );
document.write( "\r\n" );
document.write( "         for all values of x different from 0, +/-\"pi\", +/-\"2pi\", . . . \r\n" );
document.write( "\r\n" );
document.write( "         In particular,  \"1%2Ftan%5E2%28pi%2F8%29\" - \"1%2Fsin%5E2%28pi%2F8%29\"  is -1.\r\n" );
document.write( "
\r
\n" ); document.write( "\n" ); document.write( "Solved for much more general expression, in simplest possible way, in 3 lines with complete explanations.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "
\n" );