document.write( "Question 593813: how do I find the equation of the line with a slope -1 that is tangent to the curve y=1/x-1?\r
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document.write( "I don't think there is a solution to this since there are two curves and the y-axis is a vertical asymptote.\r
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document.write( "Any help is greatly appreciated. \n" );
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Algebra.Com's Answer #376468 by nerdybill(7384)![]() ![]() You can put this solution on YOUR website! how do I find the equation of the line with a slope -1 that is tangent to the curve y=1/x-1? \n" ); document.write( "Find the derivative of: \n" ); document.write( "y=1/x-1 \n" ); document.write( "y=x^(-1)-1 \n" ); document.write( "y' = -x^(-2) \n" ); document.write( "y' = -1/x^2 \n" ); document.write( ". \n" ); document.write( "Set y' to -1 and solve for x: \n" ); document.write( "y' = -1/x^2 \n" ); document.write( "-1 = -1/x^2 \n" ); document.write( "x^2 = 1 \n" ); document.write( "x = {-1, +1} \n" ); document.write( ". \n" ); document.write( "Using x=1, find y: \n" ); document.write( "y=1/x-1 \n" ); document.write( "y=1/1-1 \n" ); document.write( "y=1-1 \n" ); document.write( "y=0 \n" ); document.write( "so, the point at which the slope is -1 is at (1,0) \n" ); document.write( ". \n" ); document.write( "equation of line, plug into the \"point-slope\" form: \n" ); document.write( "y - y1 = m(x - x1) \n" ); document.write( "y - 0 = -1(x - 1) \n" ); document.write( "y = -x + 1 (this is what they're looking for) \n" ); document.write( " \n" ); document.write( " |