Question

question 5 given the function $f(r)=(r - 7)(r + 3)(r - 1)$ its $f$-intercept is its $r$-intercepts are

Explanation:

Step1: Find the f - intercept

Set $r = 0$ in the function $f(r)$.
$f(0)=(0 - 7)(0 + 3)(0 - 1)=(-7)\times3\times(-1)=21$

Step2: Find the r - intercepts

Set $f(r)=0$. Then $(r - 7)(r + 3)(r - 1)=0$.
By the zero - product property, if $ab = 0$, then $a = 0$ or $b = 0$. So $r-7=0$ gives $r = 7$, $r + 3=0$ gives $r=-3$, and $r - 1=0$ gives $r = 1$.

Answer:

The $f$-intercept is $21$.
The $r$-intercepts are $7,-3,1$.