How do you divide #(7x^4 - 4x^2 – 36x+ 81 )/((x + 9) )#?

1 Answer
Jan 3, 2016

#7x^4-4x^2-36+81#

#= (x+9)(7x^3-63x^2+563x-5103)+46008#

Explanation:

I like to long divide the coefficients, not forgetting to include a #0# for any missing power of #x# (in this case #x^3#)...

enter image source here

Long division of coefficients is similar to long division of numbers.

We find:

#7x^4-4x^2-36+81#

#= (x+9)(7x^3-63x^2+563x-5103)+46008#

That is #(7x^4-4x^2-36+81)# divided by #(x+9)# results in a quotient #(7x^3-63x^2+563x-5103)# with remainder #46008#.