The domain of a function A domain of a function is the set of all inputs - inputs over which the function is defined - over which the function is defined, This is the domain - the domain of a function - Actually let me write that out. So the domain of thisįunction f would be all real numbers except for x equals 0. So this gets to the essence of what domain is. This function definition does not tell us what to actually do with 0. Does thisĭefinition tell us what we need to output? So if I attempt to put x equal 0, then thisĭefinition would say f of 0 be 2 over 0, but 2 over 0 is The function tells us what we need to output. Let's attempt to input 0 into the function. If our input was pi, then we input into our function and thenį of pi - when x is pi, we're going to outputį of pi, which is equal to 2 over pi. So we're able, for that input, we'reĪble to find an output. Well, f of 3 that we're going to output - we have, we
So in this case if - let me see - that's my function f. We have the function - let's say we have the function f of x is equal to 2 over x. Here and it takes inputs, and for a given input, it's going to So function we can view as something - so I put a function in this box Let's have a little bit of a review of whatĪ function is before we talk about what it means that what the domain of a function means.
