How do you find the domain of y = 3/x?

1 Answer
MathFact-orials.blogspot.com
Oct 20, 2017

x!=0

Explanation:

The Domain is the list of allowable values of x. I find it easiest to first say x is all values and then find any that x can't be. So - are there any values that x can't be?

The answer is yes: x!=0 because that would make the fraction divisible by 0 and that is a no-no.

We can express this in a few different ways. One way is to simply write x!=0. Another is to write (-oo,0), (0,oo). And there are others that have more rigorous notation.

Here's a graph to see the disallowed value of x:

graph{3/x[-10,10,-100,100]}

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