Question Number 171301 by mpakhrur last updated on 12/Jun/22
$$\int_{\mathrm{1}} ^{\mathrm{2}} \mathrm{6}{x}^{\mathrm{2}} −\mathrm{2}{x}+\mathrm{3} \\ $$
Commented by Kalebwizeman last updated on 12/Jun/22
$$\left.\frac{\mathrm{6}{x}^{\mathrm{3}} }{\mathrm{3}}−\frac{\mathrm{2}{x}^{\mathrm{2}} }{\mathrm{2}}+\mathrm{3}{x}\right]\underset{\mathrm{1}} {\overset{\mathrm{2}} {\:}}\: \\ $$$$\left.\mathrm{2}{x}^{\mathrm{3}\:} −{x}^{\mathrm{2}} +\mathrm{3}{x}\right]\underset{\mathrm{1}} {\overset{\mathrm{2}} {\:}} \\ $$$$=\left[\mathrm{2}\left(\mathrm{2}\right)^{\mathrm{3}} −\left(\mathrm{2}\right)^{\mathrm{2}} +\mathrm{3}\left(\mathrm{2}\right)\right]−\left[\mathrm{2}\left(\mathrm{1}\right)^{\mathrm{3}} −\left(\mathrm{1}\right)^{\mathrm{2}\:} +\mathrm{3}\left(\mathrm{1}\right)\right] \\ $$$$=\left(\mathrm{16}−\mathrm{4}+\mathrm{6}\right)−\left(\mathrm{2}−\mathrm{1}+\mathrm{3}\right) \\ $$$$=\mathrm{18}−\mathrm{4} \\ $$$$=\mathrm{14} \\ $$