document.write( "Question 1186948: Prove that \r
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Algebra.Com's Answer #817909 by MathLover1(20850) $\"\"$ $\"About$

You can put this solution on YOUR website!
prove:\r
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\n" ); document.write( "\n" ); document.write( "manipulate left side\r
\n" ); document.write( "\n" ); document.write( " $\"%28tan%28A%29+-+tan%28B%29%29%2F%281+-+tan%28A%29tan%28B%29%29\"$ ..........use identity $\"tan%28A%29+=1%2Fcot%28A%29+\"$ , $\"tan%28B%29+=1%2Fcot%28B%29+\"$ \r
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\n" ); document.write( "\n" ); document.write( "= $\"%281%2Fcot%28A%29-+1%2Fcot%28B%29%29%2F%281-%281%2Fcot%28A%29%29%281%2Fcot%28B%29%29%29+\"$ \r
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..........simplify\r
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\r
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\n" ); document.write( "\n" ); document.write( "= $\"%28cot%28B%29+-cot%28A%29%29%2F%28cot%28A%29cot%28B%29+-+1%29+\"$ \r
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