document.write( "Question 871953: If the two roots of the equation: X^2+X-3=0 are M and N:\r
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document.write( "a. Form the equation that has the roots 1/M, 1/M.
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document.write( "b. Form the equation that has the roots M^2, N^2. \n" );
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Algebra.Com's Answer #525953 by jim_thompson5910(35256)![]() ![]() ![]() You can put this solution on YOUR website! \n" ); document.write( "If the two roots of the equation: x^2+x-3=0 are m and n, then\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "(x-m)(x-n) = x^2+x-3 \n" ); document.write( "x^2-xm-xn+mn = x^2+x-3 \n" ); document.write( "x^2-(m+n)x+mn = x^2+x-3\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Equate coefficients to get\r \n" ); document.write( "\n" ); document.write( "-(m+n) = 1 which leads to m+n = -1 \n" ); document.write( "mn = -3\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Now square both sides and isolate m^2 + n^2\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "m+n = -1 \n" ); document.write( "(m+n)^2 = (-1)^2 \n" ); document.write( "(m+n)^2 = 1 \n" ); document.write( "m^2 + 2mn + n^2 = 1 \n" ); document.write( "m^2 + 2(-3) + n^2 = 1 ... plug in mn = -3 \n" ); document.write( "m^2 - 6 + n^2 = 1 \n" ); document.write( "m^2 + n^2 = 1 + 6 \n" ); document.write( "m^2 + n^2 = 7\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "-------------------------------------------------------------------------------------------- \n" ); document.write( "a) If the roots are 1/m and 1/n, then...\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "(x - 1/m)(x - 1/n) \n" ); document.write( "x^2 - x/m - x/n + 1/mn \n" ); document.write( "x^2 - (1/m + 1/n)x + 1/mn \n" ); document.write( "x^2 - (n/mn + m/mn)x + 1/mn \n" ); document.write( "x^2 - ((n + m)/mn)x + 1/mn \n" ); document.write( "x^2 - ((m + n)/mn)x + 1/mn \n" ); document.write( "x^2 - ((-1)/mn)x + 1/mn \n" ); document.write( "x^2 - ((-1)/(-3))x + 1/(-3) \n" ); document.write( "x^2 - (1/3)x - 1/3\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "If the roots are 1/m and 1/n, then the polynomial is x^2 - (1/3)x - 1/3\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "-------------------------------------------------------------------------------------------- \n" ); document.write( "b) If the roots are m^2 and n^2, then \r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "(x - m^2)(x - n^2) \n" ); document.write( "x^2 - xn^2 - xm^2 + m^2n^2 \n" ); document.write( "x^2 - (n^2 + m^2)x + (mn)^2 \n" ); document.write( "x^2 - (m^2 + n^2)x + (mn)^2 \n" ); document.write( "x^2 - (7)x + (-3)^2 \n" ); document.write( "x^2 - 7x + 9\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "If the roots are m^2 and n^2, then the polynomial is x^2 - 7x + 9 \n" ); document.write( " \n" ); document.write( " |