document.write( "Question 401384: Vertify is an identity
\n" ); document.write( "cos^2(2x)+4sin^2(x).cos^2(x)=1
\n" ); document.write( "

Algebra.Com's Answer #284079 by richard1234(7193)\"\" \"About 
You can put this solution on YOUR website!
Btw, it's spelled \"verify,\" not \"vertify.\" I can immediately determine who wrote each problem based on the spelling...\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Anyway, we can write \"4%2Asin%5E2%28x%29cos%5E2%28x%29\" as \"%282%2Asin%28x%29cos%28x%29%29%5E2\". Applying double-angle formula for sine, this is equal to \"sin%5E2%282x%29\". Therefore the expression is equal to \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"cos%5E2%282x%29+%2B+sin%5E2%282x%29\", which is equal to 1 by the Pythagorean identity.
\n" ); document.write( "
\n" );