In its simplest form the domain is all the values that go into a function, and the range is all the values that come out. But in fact they are very important in defining a function.
Domain are all the x-values which have to be put in a function. In short, It can be called INPUT. Hence, Domain is important for a function so that an output can be gotten from that function.
<u>Range (Output):</u>
Range are all the y-values which are given from the function as a OUTPUT or RESULT. Hence, An OUTPUT is important when we give an INPUT.