How do you divide ( 2x^4 - 3x^3 - 5x^2+17x+1 )/(x^2 - x )2x43x35x2+17x+1x2x?

1 Answer
Jan 6, 2018

I'd like to use long division here. If you're not familiar with this method, I recommend this guide

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color(white)(.).

color(white)(x^2-x | -) x2x color(white)(2x^4-3x^3.)2x43x3. 2x^2-x-62x2x6
color(white)(x^2-x)x2x . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .................................
x^2-x| x2x color(white)(-) 2x^4-3x^3-5x^2+17x+12x43x35x2+17x+1
color(white)(x^2-x | ) x2x color(black)(-) 2x^4-2x^32x42x3
color(white)(x^2-x | ) x2x color(white)(-) . . . . . . . . . ...........
color(white)(x^2-x | ) x2x color(white)(-) color(white)(2x^4)2x4 -1x^3-5x^21x35x2
color(white)(x^2-x | ) x2x color(white)(2x^4)2x4 color(black)(-) -1x^3+1x^21x3+1x2
color(white)(x^2-x | ) x2x color(white)(-) color(white)(2x^4)2x4 . . . . . . . . . ...........
color(white)(x^2-x | ) x2x color(white)(-) color(white)(2x^4 -1x^3)2x41x3 -6x^2 +17x6x2+17x
color(white)(x^2-x | ) x2x color(white)(2x^4 -1x^3)2x41x3 color(black)(-) -6x^2 +6x6x2+6x
color(white)(x^2-x | ) x2x color(white)(-) color(white)(2x^4-6x^2)2x46x2 . . . . . . . . . ...........
color(white)(x^2-x | ) x2x color(white)(-) color(white)(2x^4 -1x^3-6x^2. .)2x41x36x2.. 11x +111x+1

We can't keep dividing because the divisor (x^2-xx2x) has a greater power (exponent) than the remainder (11x+111x+1) So, this is our equation: 2x^2-x-6+(11x+1)/(x^2-x)2x2x6+11x+1x2x

Note, we tacked on the remainder, divided by the original equation. This is essential!

To double check our work, we can graph the original problem and our new equation and see if they are the same