化簡:\( \frac{11}{2} x^{2} y-\frac{9}{4} x y^{2}+\frac{1}{4} x y-\frac{1}{14} y^{2} x+\frac{1}{15} y x^{2}+\frac{1}{2} x y \).
已知
\( \frac{11}{2} x^{2} y-\frac{9}{4} x y^{2}+\frac{1}{4} x y-\frac{1}{14} y^{2} x+\frac{1}{15} y x^{2}+\frac{1}{2} x y \).
要求
化簡給定表示式。
解答
我們知道,表示式中可以對同類項進行加減運算。
因此,
$\frac{11}{2} x^{2} y-\frac{9}{4} x y^{2}+\frac{1}{4} x y-\frac{1}{14} y^{2} x+\frac{1}{15} y x^{2}+\frac{1}{2} x y=(\frac{11}{2}+\frac{1}{15})x^2y-(\frac{9}{4}+\frac{1}{14})xy^2+(\frac{1}{4}+\frac{1}{2})xy$
$=\left(\frac{11\times 15+1\times 2}{30}\right) x^{2} y-\left(\frac{9\times 7+1\times 2}{28}\right) xy^{2} +\left(\frac{1+1\times 2}{4}\right) xy$
$=\left(\frac{165+2}{30}\right) x^{2} y-\left(\frac{63+2}{28}\right) xy^{2} +\left(\frac{1+2}{4}\right) xy$
$=\frac{167}{30} x^{2} y-\frac{65}{28} xy^{2} +\frac{3}{4} xy$.
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