Chapter 8.9, Problem 3ST

To determine

To find: the zero to the nearest tenth.

Answer to Problem 3ST

The real zero is $r=-1.7$ .

Explanation of Solution

Given information:

The polynomial is $P\left(x\right)=x^3+5$ .

Calculation: to find the real zero, first find the polynomial function values,

$x$	$P\left(x\right)$
$0$	$5$
$-1$	$4$
$-2$	$-3$

From the above table it can be observed that the polynomial zero can be lie in between $\left(-1\right)-\left(-2\right)$ , so now find the polynomial function values between $\left(-1\right)-\left(-2\right)$ ,

$x$	$P\left(x\right)$
$-1.5$	$1.625$
$-1.6$	$0.904$
$-1.8$	$-0.832$

Thus, the real zero of polynomial must be $r=-1.7$ .