Determine the real roots of $f(x)=x^5-8x^4+44x^3-91x^2+85x-26$

$($a$)$ Graphically. Please provide the commands you used as well as your outputs $($i$.$e$.$ graph and the root$).$

$($b$)$ Iteratively by employing the initial guesses of $x_{\text{I}}=0\mathrm{.}5$ and $x_u=1,0.$ Please provide the commands you used as well as your output root. Solve the problem with mathlab commands