(2).f(x)= radical number x 2; x∈R

(3).f(x)=6/x^2-3x+2； X is not equal to 1 or 4.

(4).f(x)= radical number 4-x/x- 1 1≤x≤4.

2. Name the domain and value domain of the following functions.

( 1).y=3x x∈R，y∈R

(2).y=8/x x is not equal to 0, and y is not equal to 0.