I need help with math?

Question

ok i'm taking pre-cal and its freakin hard i have a big test on friday and i need help. i'm having trouble with these f(x)= equations there called like f of x or something. i never learned them. can any one help?

Answer 1

hiya, this isnt so bad, I am going to attempt to explain this, but it may be difficult without some pointing and handwaving.

f(x) is read f of x, this means we are going to call the equation f (we used to say it was y=equation, but here we are going to call it f) and f is going to be made up of terms consisting "of x".

so as an example we are going to make an equation consisting of the variable f

f(x)= x^2+3x-4

now, you are told to complete charts or evaluate at x =3 or something like this...well is what that means is to plug the number in the equation everywhere you see an x

so...

f(3) = (3)^2 +3(3) - 4
f(3) = 9 +3 - 4
f(3)=8

anyway, hope this helps you
matttlocke

Answer 2

Partial plot of a function f. Each real number x is associated with the number f(x) = x3 − 9x.In mathematics, a function relates each of its inputs to exactly one output. A standard notation for the output of the function f with the input x is f(x). The set of all inputs that a function accepts is called the domain of the function. The set of all outputs is called the range.

For example, the expression f(x) = x2 describes a function, f, that relates each input, x, with one output, x2. Thus, an input of 3 is related to an output of 9. Once a function, f, has been defined, we can write, for example, f(4) = 16.

It is a usual practice in mathematics to introduce functions with temporary names like f; When a name for the function is not needed, often the form y=x2 is used.

Also see my sources for more details.

Answer 3

example:
f(x)=10x-2
it is the same as
y=10x-2


the only reason they put (X)...which means that plug in any number to the x and see how your equation will look like.

exp:

f(2)=10(2)-2

the equation as above,but instead of" x"i plugged in a number
simple..

Answer 4

f(x) just means that you have a function and x is the independent variable. f(x) = 3x is the same as y = 3x; it's just another way to write it.

Answer 5

f(x)=fof(x) is called compose function.
such, f0f(x)=f[f(x)]
Exemple:
f(x)=x-3 , f1(x)=5x
f0f1(x)=f[f1(x)]
f0f1(x =f[5x)]
'' =5f(x)=5(x-3)
f0f1(x)=5x-15 or 5(x-3)
(simple exemple)
good luck

Answer 6

f(x)=equation
is same thing as
y=equation