解:根據(jù)表格數(shù)據(jù),在平面直角坐標(biāo)系中描出點(diǎn)$\left(\dfrac{1}{4},\dfrac{21}{4}\right)$、$\left(\dfrac{1}{2},\dfrac{7}{2}\right)$、$(1,3)$、$\left(2,\dfrac{7}{2}\right)$、$\left(4,\dfrac{21}{4}\right),$然后用平滑曲線連接這些點(diǎn),即可得到函數(shù)$y=x+\dfrac{1}{x}+1(x>0)$的大致圖象(如圖所示)。通過觀察函數(shù)$y=x+\dfrac{1}{x}+1(x>0)$與正比例函數(shù)$y_1=3x(x\geq0)$的圖象交點(diǎn),可得當(dāng)$x>1$時(shí),$y_1>y。$