Could someone explain to me how to find the domain of a function such as (f+g)(x) = (x^3 + 2x^2) + (3x^2 - 1)?

Question

This was explained to us in class, but I didn't quite understand how to do it and there is no tutor available for summer classes.

Answer 1

these kinda functions are distributive
that is u can write it as f{x}+g{x}
by comparin this with the rhs u observe that it is in the same format
so the domain which is all the possible values of "x" for which this function can be defined is the whole set of real numbers
as all real numbers have 3rd and 2nd powers

Answer 2

The domain of a function is all the real numbers -except- those points where the function is undefined. There are very few ways that a function can be undefined; the only one you're likely to see in an introductory course is when you have to divide by zero to evaluate the function. Dividing by zero is not a mathematically defined operation, and so you cannot evaulte the function at that point.

Your problem, the addition of two simple polynomial equations, is defined for all real numbers because you are never forced to divide by zero at any point.

If one term had a denominator such as (x-1) then the domain would be all Reals except x=1, since at that point, the denominator is zero, and the function is undefined.

Answer 3

1/2

Answer 4

The domain of any function is all the possible values of X. Any value of X that results in division by 0 or in taking an even root of a negative number (ie. the square root of -1 or the 4th root of -1) will result in an unreal or undefined solution...therefore these values of X must be exclude. Since your function doesn't involve either of the exceptions I've mentioned, your domain is all real numbers.

Answer 5

Type it into "Google"