A community for students.
Here's the question you clicked on:
 0 viewing
anonymous
 one year ago
If f(x) = x2 – 1 and g(x) = 2x – 3, what is the domain of (f*g)(x)
anonymous
 one year ago
If f(x) = x2 – 1 and g(x) = 2x – 3, what is the domain of (f*g)(x)

This Question is Closed

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1you are multiplying a polynomial times another polynomial. This will give you a polynomial as well.

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1You know what polynomial is, correct?

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1Ok, will you agree with me (if you don't understand why it is so, then ask! but will you agree) that a polynomial is DEFINED for ALL values of x?

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1Ok, i will post a percise and short definition of a polynomial. "Polynomial" is a function that can have the terms of: 1) Constants (some real numbers) 2) x raised to a power of 1, 2, 3 and on (but the power has to be a whole number) (and the terms can have any real coefficients)

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1i will do some examples

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1polynomials. examples. y=0 y=45 y=√3 (or any function y=c where c is a constant) y=4x y=3x+2 y=x9 (or any function in a form of y=mx or y=mx+b) y=3x² y=5x²+9 y=x²+8 y=x²7x7 and so on....

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0ok im pretty sure i get it

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1it (a polynomial) terms can be made up and can consist of any terms as long as the terms have x^(whole number) and other real numbers ok got the definition

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1So, really try to think of any polynomial that can have an UNDEFINED XVALUE. what I mean by "UNDEFINED XVALUE" is that if you plug this value for x into the function, then you will get an undefined/indeterminate output for y in polynomials this "UNDEFINED XVALUE" never exists

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1Because if your x's have only whole number powers such as: x\(^1\), x\(^2\), x\(^3\), x\(^4\) then you will get a valid result NO MATTER WHAT you plug in for x.

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1now agin, when you multiply two functions where both of these functions are polynomials (i.e. whole number powers of x like 1, 2, 3 and on with or without constants) then you get after multiplying these two (or any number of) polynomial functions  you will get  a polynomial function (whole number powers of x like 1, 2, 3 and on with or without constants)

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1polynomial • polynomial = polynomial it is good to remember, even if you don't fully comprehend the deepness behind it (you will get it at some time)

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1now, if your function f(x)=x²1 and g(x)=2x3 polynomial?

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1are the polynomials?

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1so the product of them (when you multiply f • g) will also give you a what?

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1And again, ANY POLYNOMIAL has a domain of ALL VALUES OF X. (in interval notation: Domain: (∞, +∞) )

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1So will what be the domain of your new function be? (we know your new function is going to be a polynomial as we said b4)

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1if you got questions, you can always ask ....

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0im following as of right now :)

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1we know your function is a polynomial (correct?) So can you give me the domain of your new function, or not yet?

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1the ∞ (or +∞) symbol means infinity and ∞ means negative infinity > (same stength but going the negative way)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0okay i remember that one

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1(∞, +∞) means from negative infinity to positive infinity and that is: every single number that there can possible be

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0i wish you were my math teacher haha

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1that is the domain of your new polynomail function, or of any polynomial function.....

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1i am just some 19 yrs old dude....

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.1Math is just something I like:) In any case, do you have questions regarding this question?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0nope i got it :) ty so much
Ask your own question
Sign UpFind more explanations on OpenStudy
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.