SOLUTION: 1.Divide using polynomials long division. (3x^2-29x+56)/(x-7) 2.Use the polynomial remainder theorem to evaluate the polynomial. f(x)=x^3-4x^2-12x+15 what is the

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: 1.Divide using polynomials long division. (3x^2-29x+56)/(x-7) 2.Use the polynomial remainder theorem to evaluate the polynomial. f(x)=x^3-4x^2-12x+15 what is the      Log On


   

Question 1056365: 1.Divide using polynomials long division.
(3x^2-29x+56)/(x-7)
2.Use the polynomial remainder theorem to evaluate the polynomial.

f(x)=x^3-4x^2-12x+15
what is the value of f(6)?
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
===3x-8
x-7/3x^2-29x+56
==3x^2-21x
change sign and add
======-8x+56
======-8x+56
change signs and add. It is 0.
(x-7)(3x-8)
x=8/3
f(8/3) should be 0
3*(64/9)-29(8/3)+56=(192/9)-(696/9)+(504/9)=0
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F(6)=6^3-4(6^2)-72+15=216-144-57
=15. The graph shows when x=6, y=15 by inspection.
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graph%28300%2C300%2C-10%2C10%2C-10%2C20%2Cx%5E3-4x%5E2-12x%2B15%29