document.write( "Question 66123: I need to solve for all real roots\r
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document.write( "(sqrt)z-(sqrt)(z-1)=1 \n" );
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Algebra.Com's Answer #46860 by ptaylor(2198)![]() ![]() You can put this solution on YOUR website! I need to solve for all real roots\r \n" ); document.write( "\n" ); document.write( "(sqrt)z-(sqrt)(z-1)=1\r \n" ); document.write( "\n" ); document.write( "First, we'll square both sides to start getting rid of the radicals:\r \n" ); document.write( "\n" ); document.write( "[sqrt(z)-sqrt(z-1)]^2=(sqrt(z))^2-2(sqrt(z))(sqrt(z-1))+(sqrt(z-1))^2\r \n" ); document.write( "\n" ); document.write( "so we have:\r \n" ); document.write( "\n" ); document.write( "z-2sqrt((z)(z-1))+z-1=1 which equals\r \n" ); document.write( "\n" ); document.write( "2z-1-2sqrt((z)(z-1))=1 Now, we'll subtract 2z and -1 from both sides:\r \n" ); document.write( "\n" ); document.write( "-2sqrt((z)(z-1))=1-2z+1=\r \n" ); document.write( "\n" ); document.write( "-2sqrt((z)(z-1))=2-2z divide both sides by -2\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "sqrt((z)(z-1))=z-1 square both sides again:\r \n" ); document.write( "\n" ); document.write( "(z)(z-1)=(z-1)(z-1) \r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Note: We are to this point and the tendency is to divide both sides by (z-1) and that would be a BIG mistake. Why??????????????\r \n" ); document.write( "\n" ); document.write( "(z)(z-1)=(z-1)(z-1)= \n" ); document.write( "z^2-z=z^2-2z+1 subtract z^2 and -2z from both sides:\r \n" ); document.write( "\n" ); document.write( "z^2-z^2-z+2z=1\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "z=1 is the only real solution:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "AN IMPORTANT LESSON HERE:\r \n" ); document.write( "\n" ); document.write( "z-1=0 AND YOU CAN'T DIVIDE BY 0\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Hope this helps-----ptaylor\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |