#### Answer

(a) $f(x)=2x+1$
(b) $f(x) = x^4$
(c) $f(x)=3^x$
(d) $f(x) =-x^2+3x-4$
(e) $f(x) =3x^5+x^2-3$
(f) $f(x)=\frac{2x^4+3x^3+4}{1-x^2}$

#### Work Step by Step

(a) This function is of the general form of $f(x)=ax+b$ where $a$ and $b$ are real constants
(b) This function is of the form of $f(x)=x^a$ where $a$ is a real constant.
(c) This function is of the form of $f(x)=b^x$ where
$b>0$ and $b\neq 1$.
(d) This function is of the form of
$f(x) = ax^2+bx+c$ where $a,b$ and $c$ are constants
(e) This function is of the form of $f(x)=a_nx^n+a_{n-1}x^{n-1}+\ldots a_1x+a_0$, where $n$ is nonnegative integer, $a_0,a_1,\ldots a_n$ are real constants.
(f) This function is a ratio of two polynomials.