[填空题]
Consider the region xwy6o,;x h qh9ww-. gy2awet8i ivr9* R enclosed by the curve $y=-3(x-2)(x-8)$ and the x axis.
1. Sketch the curve and shade the region R on the following axes.
2. 1. Write down an integral that represents the area of region R ;The area of region
R is determined by A=$\int_{2}^{8}-a(x-2)(x-b) \mathrm{d} x$ ;a= ,b= .
2. Find the area of region R is units$^2$.
3. Estimate the area of region R using five trapezoids.
4. Find the percentage error between the exact value found in part (b)(ii) and the estimation in part (c);The percentage error between the estimation in part (c) and the exact value in part (b)(ii) can be found using the percentage error formula [% error]= %