How do you divide (x^2-5x-5x^3+x^4)div(5+x) using synthetic division?

1 Answer
Dec 5, 2016

The remainder is =1300 and the quotient is =x^3-10x^2+51x-260

Explanation:

Rearrange the polynomials in decreasing powers of x

Let's do the long division

color(white)(aaaa)x^4-5x^3+x^2-5xcolor(white)(aaaa)x+5

color(white)(aaaa)x^4+5x^3color(white)(aaaaaaaaaaaaa)x^3-10x^2+51x-260

color(white)(aaaa)0-10x^3+x^2

color(white)(aaaaaa)-10x^3-50x^2

color(white)(aaaaaaaaaa)0+51x^2-5x

color(white)(aaaaaaaaaaaa)+51x^2+255x

color(white)(aaaaaaaaaaaaaaaa)0-260x

color(white)(aaaaaaaaaaaaaaaaaa)-260x-1300

color(white)(aaaaaaaaaaaaaaaaaaaaaaa)0+1300

You can use the remainder theorem

f(x)=x^4-5x^3+x^2-5x

f(-5)=625+625+25+25=1300