Learn Before
Example

Finding (fg)(x)(f-g)(x) for f(x)=3x25x+7f(x) = 3x^2 - 5x + 7 and g(x)=x24x3g(x) = x^2 - 4x - 3

To calculate the difference between the polynomial functions f(x)=3x25x+7f(x) = 3x^2 - 5x + 7 and g(x)=x24x3g(x) = x^2 - 4x - 3, use the subtraction operation defined as (fg)(x)=f(x)g(x)(f - g)(x) = f(x) - g(x). First, substitute the specific polynomial expressions into the formula, resulting in (3x25x+7)(x24x3)(3x^2 - 5x + 7) - (x^2 - 4x - 3). Next, distribute the negative sign across the second polynomial, which reverses the sign of each of its terms to yield 3x25x+7x2+4x+33x^2 - 5x + 7 - x^2 + 4x + 3. Rearrange the expression so that like terms are adjacent: 3x2x25x+4x+7+33x^2 - x^2 - 5x + 4x + 7 + 3. Finally, combine these like terms by adding their coefficients to obtain the simplified difference: (fg)(x)=2x2x+10(f - g)(x) = 2x^2 - x + 10.

0

1

Updated 2026-05-26

Contributors are:

Who are from:

Tags

OpenStax

Intermediate Algebra @ OpenStax

Ch.5 Polynomials and Polynomial Functions - Intermediate Algebra @ OpenStax

Algebra

Related
Learn After