God math is sooo hard u guys and I am on my last 2 problems.. it says to
Divide using long division.
25 x^3+40x^2+21x+15 divided by -5x -4
Given functions f and g, determine the domain of f + g.
f(x) = 2x - 9, g(x) = 5 over x+8
thanks so much for your help!!
2007-07-01 12:23:58 · 2 answers · asked by JANICE 1 in Science & Mathematics ➔ Mathematics
25x^3 / -5x = -5x²
-5x²(-5x - 4) = 25x^3 + 20x²
25x^3 + 40x² + 21x + 15
25x^3 + 20x²
--------------------------------- .... subtract
.............20x² + 21x + 15
20x² / -5x = -4x
-4x(-5x - 4) = 20x² + 16x
20x² + 21x + 15
20x² + 16x
---------------------
............5x + 15
5x / -5x = -1
-1(-5x - 4) = 5x + 4
5x + 15
5x + 4
----------
....... 11
so you get -5x² - 4x - 1, remainder 11.
There's a neater way to write it, but that doesn't show the steps.
f+g = 2x - 9 + 5/(x+8) has a domain that's all real numbers except -8, which would make the bottom of the fraction 0 and hence the function undefined.
2007-07-01 12:46:33 · answer #1 · answered by Philo 7 · 1⤊ 0⤋
what grade r u in
i have no clue
2007-07-01 19:36:29 · answer #2 · answered by bclittlebear 1 · 0⤊ 1⤋