document.write( "Question 102977: The graph of the polynomial function f(x)- Ax^3+Bx^2+Cx+D,
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document.write( "where and A,B,C,and D are integers, has 3 x-intercepts at 1,2,and -6.
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document.write( "If the graph passes thought the point M(3,18),
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document.write( "determine the values of A,B,C and D. \n" );
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Algebra.Com's Answer #74899 by Fombitz(32388)![]() ![]() You can put this solution on YOUR website! An x intercept is a where f(x)=0. \n" ); document.write( "1. \n" ); document.write( "2. \n" ); document.write( "3. \n" ); document.write( "and you know that \n" ); document.write( "4. \n" ); document.write( "Using the equations you get \n" ); document.write( "1. \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "2. \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "3. \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "4. \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "Four equations, four unknowns. \n" ); document.write( "Since you didn't specify a method to choose, I'll choose a matrix method, if that's OK. \n" ); document.write( "These equations can be represented as three matrices G, U, and V. \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "where [G]x[U]=[V] \n" ); document.write( "Then [U]=[G]inv x [V] \n" ); document.write( "Find the inverse of [G](using EXCEL) and multiply by [V] \n" ); document.write( "The inverse of G is \n" ); document.write( " \n" ); document.write( "Since [V] has all values of zero except the last value. The solution matrix,[U], is 18 multplied by the last column of the inverse matrix or \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " |