How do you divide (-4x^3-15x^2-4x-12)/(x-4) ?

1 Answer
Jul 20, 2018

The remainder is =-524 and the quotient is =-4x^2-31x-128

Explanation:

Let's perform the synthetic division

color(white)(aaaa)4|color(white)(aaaa)-4color(white)(aaaa)-15color(white)(aaaaaa)-4color(white)(aaaaa)-12

color(white)(aaaaa)|color(white)(aaaa)color(white)(aaaaaaa)-16color(white)(aaaa)-124color(white)(aaaa)-512

color(white)(aaaaaaaaa)_________

color(white)(aaaaaa)|color(white)(aaaa)-4color(white)(aaaa)-31color(white)(aaaa)-128color(white)(aaaa)color(red)(-524)

The remainder is =-524 and the quotient is =-4x^2-31x-128

ALSO,

Apply the remainder theorem

When a polynomial f(x) is divided by (x-c), we get

f(x)=(x-c)q(x)+r

Let x=c

Then,

f(c)=0+r

Here,

f(x)=-4x^3-15x^2-4x-12

Therefore,

f(4)=-4*4^3-15*4^2-4*4-12

=-256-240-16-12

=-524

The remainder is =-524