functions on a graph?

Question

ive been kinda sick the past few days and havent really concentrated in algebra II, i need to know about finding the domain and range of a function on a graph. the teacher was saying something about imagining lightbulbs and seeing what the lines would cast a shadow on...or something like that?

Answer 1

All the domain of a function is is the x-value, and all the range is is the y-value. You usually won't be asked to find the range of a function because y is dependent on x, but here is an example of finding the domain of a function:

y=2x+3

In this case, the domain, x, is all real numbers, because you can substitue any value for x and get a valid output for y.

But, if you have something like this:

y= 3/(x-5)

x is all real numbers *except* 5, because you can't have a zero in the denominator.

Likewike, when given something like this:
_______
\| x - 10

x is all real numbers greater than or equal to 10, because the number under the radical can't end up being less than zero; you can't take the square root of a negative number.

The short way of putting it is to ask yourself, "What can x *not* be?" and then writing out the notation accordingly, depending on how your teacher instructs.

You can also use sites like math.com and purplemath for questions.

:D

Answer 2

All you should do is exchange the numbers for x. Your formulation is f(x)=5-3x. case in point selection a million says f(a million)=5-3x so as which you would be able to understand that x=a million. so which you recognize that the answer to volume one is 5-3(a million)=2 (2 is the respond.)

Answer 3

Make more effort to read your text and notes thorughly. Study the examples & summaries. Then get back to us with a more detailed explanation if necessary.

Answer 4

I can not understand your question .what kind of function are you trying to make?
your explanation is more similar to a physical experiment.??