document.write( "Question 1074684: Marty is proving that the following trigonometric identity is true:\r
\n" ); document.write( "\n" ); document.write( "tan^2θ⋅cos^2θ=1−cos^2θ\r
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\n" ); document.write( "\n" ); document.write( "Which step would be the first line of his proof?\r
\n" ); document.write( "\n" ); document.write( "tan^2θ⋅cos^2θ=1−sin^2θ\r
\n" ); document.write( "\n" ); document.write( "tan^2θ⋅cos^2θ=tan^2θ\r
\n" ); document.write( "\n" ); document.write( "tan^2θ⋅cos^2θ=sin^2θ\r
\n" ); document.write( "\n" ); document.write( "tan^2θ=1−cos^2θ⋅cos^2θ
\n" ); document.write( " \n" ); document.write( "

Algebra.Com's Answer #689348 by ikleyn(52866) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "Marty is proving that the following trigonometric identity is true:\r
\n" ); document.write( "\n" ); document.write( "tan^2θ⋅cos^2θ=1−cos^2θ\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Which step would be the first line of his proof?\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "

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document.write( "tan^2θ⋅cos^2θ=1−sin^2θ\r\n" );
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document.write( "tan^2θ⋅cos^2θ=tan^2θ\r\n" );
document.write( "\r\n" );
document.write( "tan^2θ⋅cos^2θ=sin^2θ     <<<---+++ This one.\r\n" );
document.write( "\r\n" );
document.write( "tan^2θ=1−cos^2θ⋅cos^2θ\r\n" );
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