# Thread: need help with some questions quicklyyyy thanks

1. ## need help with some questions quicklyyyy thanks

hi please i have to hand my assignment in by tomorrow and i don't know how to get started on some of the questions

1) if f(x) = x^2 + 5, find f(x+1) - f(x)

I have no idea how to even begin here

2) Find the domains of the following functions.

a) f(x) = 2x-37, do we just find a value for which the equation equals zero so x can be any real number except that one?

3) divide 3a^2/ a^2 - b^2 by a/ a + b
thanks i really need help quickly with question 1 and 3

2. Originally Posted by mahi123
hi please i have to hand my assignment in by tomorrow and i don't know how to get started on some of the questions

1) if f(x) = x^2 + 5, find f(x+1) - f(x)

I have no idea how to even begin here
Well $\displaystyle f(x) = x^2 + 5$ so that would mean that $\displaystyle f(x + 1) = (x + 1)^2 + 5$

Originally Posted by mahi123
2) Find the domains of the following functions.

a) f(x) = 2x-37, do we just find a value for which the equation equals zero so x can be any real number except that one?
For what values of x doesn't $\displaystyle 2x - 37$ exist? There aren't any. So the domain is all real numbers.

-Dan

3. Originally Posted by mahi123
3) divide 3a^2/ a^2 - b^2 by a/ a + b
thanks i really need help quickly with question 1 and 3
$\displaystyle \displaystyle\frac{3a^2}{a^2-b^2}:\frac{a}{a+b}=\frac{3a^2}{(a+b)(a-b)}\cdot\frac{a+b}{a}=\frac{3a}{a-b}$