Consider the following function.

$f(x)=xsin(x),a=0,n=4,-0\mathrm{.}9x0\mathrm{.}9$

$($a$)$ Approximate $f$ by a Taylor polynomial with degree $n$ at the number $a.$

$T_4(x)=x^2-\frac{x^4}{6}$

$|R_4(x)|$

Enter a number.

$($c$)$ Check your result in part $($b$)$ by graphing $|R_n(x)|.$