Definition of function

Exercise

1.: Find the following rules are single values or multivalued functions．
(a): $\displaystyle{y^{2} = x, \ x > 0}$
(b): $\displaystyle{y^{3} = x^2}$
2.: Find the domain of the following functions and draw the graph of ．
(a): $\displaystyle{f(x) = \sqrt{4 - x^2}}$
(b): $\displaystyle{h(x) = \sqrt{\frac{4x^2 - 3x^3}{6x^2 + 3x}}}$
3.: Find the composition of . $(f \circ g)(x)$ and .
(a): $\displaystyle{f(x) = 2x - 1, \ g(x) = x^2 + 1}$
(b): $\displaystyle{f(x) = \left\{\begin{array}{cl} 1 - x, & x \leq 0\\ x^2, & x >... ...eft\{\begin{array}{cl} -x, & x < 1\\ 1 + x, & x \geq 1 \end{array} \right.}$
4.: Find the inverse of the following functions.．
(a): $\displaystyle{f(x) = \frac{1}{x+2}, \ -2 < x}$
(b): $\displaystyle{f(x) = x^2 + 4x - 2}$