document.write( "Question 936364: Write a cubic function that passes through the following points: (-2,0) (3,0) (-1,0) and (1,2). Explain how you got the answer \n" ); document.write( "
Algebra.Com's Answer #569803 by TimothyLamb(4379) You can put this solution on YOUR website! the general standard cubic: \n" ); document.write( "ax^3 + bx^2 + cx + d = 0 \n" ); document.write( "--- \n" ); document.write( "from the first 3 points (-2,0) (3,0) (-1,0), we have 3 roots at: \n" ); document.write( "(x + 2)(x - 3)(x + 1) \n" ); document.write( "--- \n" ); document.write( "so the equation is as follows, where k is an unknown constant: \n" ); document.write( "(x + 2)(x - 3)(x + 1) + k = 0 \n" ); document.write( "(xx - x - 6)(x + 1) + k = 0 \n" ); document.write( "xxx + xx - xx - x - 6x - 6 + k = 0 \n" ); document.write( "xxx - 7x - 6 + k = 0 \n" ); document.write( "--- \n" ); document.write( "but from the 4th point (1,2) we know that: \n" ); document.write( "xxx - 7x - 6 + k = 0 \n" ); document.write( "1*1*1 - 7*1 - 6 + k = 0 \n" ); document.write( "-12 + k = 0 \n" ); document.write( "k = 12 \n" ); document.write( "--- \n" ); document.write( "combining the constants, the equation is: \n" ); document.write( "xxx - 7x - 6 + k = 0 \n" ); document.write( "xxx - 7x - 6 + 12 = 0 \n" ); document.write( "xxx - 7x + 6 = 0 \n" ); document.write( "--- \n" ); document.write( "answer: \n" ); document.write( "x^3 - 7x + 6 = 0 \n" ); document.write( "--- \n" ); document.write( "Free algebra tutoring live chat: \n" ); document.write( "https://sooeet.com/chat.php?gn=algebra \n" ); document.write( "--- \n" ); document.write( "Solve and graph linear equations: \n" ); document.write( "https://sooeet.com/math/linear-equation-solver.php \n" ); document.write( "--- \n" ); document.write( "Solve quadratic equations with quadratic formula: \n" ); document.write( "https://sooeet.com/math/quadratic-formula-solver.php \n" ); document.write( "--- \n" ); document.write( "Solve systems of linear equations up to 6-equations 6-variables: \n" ); document.write( "https://sooeet.com/math/system-of-linear-equations-solver.php \n" ); document.write( "--- \n" ); document.write( " |