Question

How do I find the domain of this function?

Answer 1

\[g(x) \sqrt{x^2 - 3x - 40}\]

Answer 2

I have \[\sqrt{(x-8)(x+5)} \]

Answer 3

\[(x-8)(x+5) \ge 0\]

Answer 4

The original problem is at the top.

Answer 5

Draw a number line and see for it

Answer 6

I don't know what x can't be though

Answer 7

I know the answer but I don't know how to get the answer.

Answer 8

(-infinity , 5] U [8 , infinity)

Answer 9

yeah but how do I find that?

Answer 10

just do trial and error method...)

Answer 11

(x−8)(x+5)≥0

Answer 12

luk for the vlue of x which satisfies this...

Answer 13

There must be a logical way to find the answer, right?

Answer 14

(x-8)(x+5) >= 0

its a parabola, right ?

Answer 15

I could input it into my graphing calculator but other wise I don't know how to tell if its a parabola or not.

Answer 16

y = ax^2 + bx + c is a parabola

Answer 17

any quadratic function gives a parabola graph

Answer 18

ok

Answer 19

can you find the x intercepts ?

Answer 20

once you find x-intercepts, you would know where the parabola dips into x axis (goes negative)