Question

Really need help ASAP, would be SOOOO appreciated. Please show me how to do this, im so confused... Find the domain of the function.
g(x)=(x+7)/(x^3+9x)

Answer 1

find out the x values that make the denominator zero.

Answer 2

you'll prolly have to factor your expression...

Answer 3

so would -7, -3, 3 ...be correct? Sorry, im just terrible with math. :(

Answer 4

ok... let's factor that denominator...
x^3 + 9x = x(x^2 + 9)

what makes that zero? let see:
x(x^2+9) = 0

is it clear what x needs to be in order for x(x^2+9)=0 ?

Answer 5

what can you tell me about this equation: a*b = 0

Answer 6

one has to be 0

Answer 7

good...
that's excactly how i wrote the equation:
x * (x^2+9) = 0
a * b = 0

Answer 8

so either x=0 or x^2+9=0, agreed?

Answer 9

yeah/... i get it now. Thanks sooooooo much. Math is my worst subject. your the best!! =D

Answer 10

yw... the domain btw... is all real numbers except x=0...:)