Posting on the behalf of @jsmit200

Question

rebeccaxhawaii · Answer

f(x) = 9x^3 + 6x^2 − 2

mathmate · Answer

@rebeccaxhawaii 
Did you get a power of attorney from @jsmit200 ?  lol

jsmit200 · Answer

You are awesome, I just need to know the Domain and range some explanation would be wonderful.

jsmit200 · Answer

Lol, I will sign the document!

rebeccaxhawaii · Answer

That is classified information, legally im not permitted to say. @mathmate

shadowlegendx · Answer

He's having trouble posting questions @mathmate

mathmate · Answer

ok, in that case, hope all openstudiers have clearance.

mathmate · Answer

Post the question and I'll see if I can help!

rebeccaxhawaii · Answer

@mathmate this is the question

jsmit200 · Answer

f(x) = 9x^3 + 6x^2 − 2

jsmit200 · Answer

Need help finding the domain and range.

mathmate · Answer

To start with, ALL polynomials have domain of R, i.e. (-inf, +inf).

abdullahm · Answer

The domain is always all real numbers unless you have a square root or a fraction.

In that case, you will have to exclude any values of x that make the square root negative, or the fraction undefined.

abdullahm · Answer

A fraction is undefined when the denominator is 0.

jsmit200 · Answer

Gotcha. Now where would I start? Would I factor at all?

abdullahm · Answer

You wouldn't need to factor since we don't have any fractions or square roots. The domain will be all real numbers.

You would factor if you were trying to find the roots, but the question isn't interested in the roots.

jsmit200 · Answer

okay so it would be (-inf, inf)?

abdullahm · Answer

Yes

jsmit200 · Answer

Awesome. Now how would I go about finding range?

abdullahm · Answer

Since this is a quadratic equation, the graph will be similar to |dw:1464398039803:dw| The actual graph looks like: https://www.desmos.com/calculator/cmwfhdjkgi What do you think the range will be?