document.write( "Question 976580: Prove that:\r
\n" ); document.write( "\n" ); document.write( "tan(45-x) = 1-tanx/1+tanx \n" ); document.write( "

Algebra.Com's Answer #598138 by FrankM(1040) $\"\"$ $\"About$

You can put this solution on YOUR website!
There is an identity for Tangent of the difference of 2 angles - \r
\n" ); document.write( "\n" ); document.write( " $\"tan%28A-B%29=+%28tanA-tanB%29%2F%281%2BtanAtanB%29\"$ \r
\n" ); document.write( "\n" ); document.write( "here, A = 45, B = x, let's substitute :\r
\n" ); document.write( "\n" ); document.write( " $\"tan%2845-x%29=+%28tan45-tanx%29%2F%281%2Btan45tanx%29\"$ \r
\n" ); document.write( "\n" ); document.write( "and one of the tan values I know by heart is tan 45 = 1. I hope you know this. \r
\n" ); document.write( "\n" ); document.write( " $\"tan%2845-x%29=+%281-tanx%29%2F%281%2Btanx%29\"$ \r
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