Rút gọn:
1. -3x5y4 + 3x2y3 - 7x2y3 + 5x5y4
2. \(\frac{1}{2}\)x4y - \(\frac{3}{2}\)x3y4 + \(\frac{5}{3}\)x4y - x3y4
3. 5x - 7xy2 + 3x - \(\frac{1}{2}\)xy2
4. \(-\frac{1}{5}\)x4y3 + \(\frac{3}{4}\)x2y - \(\frac{1}{2}\)x2y + x4y3
5. \(\frac{7}{4}\)x5y7 - \(\frac{3}{2}\)x2y6 + \(\frac{1}{5}\)x5y7 + \(\frac{2}{3}\)x2y6
6. \(\frac{1}{3}\)x2y5 (\(-\frac{3}{5}\)x3y) + x5y6
7. \(\frac{1}{2}\)x4y ( \(-\frac{2}{3}\)x3y2) \(-\frac{1}{3}\)x7y3
8. 5xy2 (\(-\frac{3}{10}\)x2y) + \(\frac{3}{4}\)x3y3
9. \(\frac{1}{7}\)x2y3 (\(-\frac{14}{3}\)xy2) \(-\frac{1}{2}\)xy (x2y4)
10. \(\frac{2}{5}\)x4y5 (\(\frac{5}{4}\)x2y3) + \(\frac{5}{3}\)x2y3 (\(-\frac{9}{10}\)x4y5)
HELP ME T^T
BÀI HƠI DÀI NHƯNG GIÚP MK.
1.
\(-3x^5y^4+3x^2y^3-7x^2y^3+5x^5y^4\)
\(=(-3x^5y^4+5x^5y^4)+(3x^2y^3-7x^2y^3)\)
\(=2x^5y^4-4x^2y^3\)
2.
\(\frac{1}{2}x^4y-\frac{3}{2}x^3y^4+\frac{5}{3}x^4y-x^3y^4\)
\(=(\frac{1}{2}x^4y+\frac{5}{3}x^4y)-(\frac{3}{2}x^3y^4+x^3y^4)\)
\(=\frac{13}{6}x^4y-\frac{5}{2}x^3y^4\)
3.
\(5x-7xy^2+3x-\frac{1}{2}xy^2\)
\(=(5x+3x)-(7xy^2+\frac{1}{2}xy^2)\)
\(=8x-\frac{15}{2}xy^2\)
4.
\(\frac{-1}{5}x^4y^3+\frac{3}{4}x^2y-\frac{1}{2}x^2y+x^4y^3\)
\(=(\frac{-1}{5}x^4y^3+x^4y^3)+(\frac{3}{4}x^2y-\frac{1}{2}x^2y)\)
\(=\frac{4}{5}x^4y^3+\frac{1}{4}x^2y\)
5.
\(\frac{7}{4}x^5y^7-\frac{3}{2}x^2y^6+\frac{1}{5}x^5y^7+\frac{2}{3}x^2y^6\)
\(=(\frac{7}{4}x^5y^7+\frac{1}{5}x^5y^7)+(-\frac{3}{2}x^2y^6+\frac{2}{3}x^2y^6)\)
\(=\frac{39}{20}x^5y^7-\frac{5}{6}x^2y^6\)
6.
\(\frac{1}{3}x^2y^5(-\frac{3}{5}x^3y)+x^5y^6=(\frac{1}{3}.\frac{-3}{5})(x^2.x^3)(y^5.y)+x^5y^6\)
\(=\frac{-1}{5}x^5y^6+x^5y^6=\frac{4}{5}x^5y^6\)
7.
\(\frac{1}{2}x^4y(-\frac{2}{3}x^3y^2)-\frac{1}{3}x^7y^3\)
\(=(\frac{1}{2}.\frac{-2}{3})(x^4.x^3)(y.y^2)-\frac{1}{3}x^7y^3\)
\(=-\frac{1}{3}x^7y^3-\frac{1}{3}x^7y^3=\frac{-2}{3}x^7y^3\)
8.
\(5xy^2(\frac{-3}{10}x^2y)+\frac{3}{4}x^3y^3\)
\(=(5.\frac{-3}{10})(x.x^2)(y^2.y)+\frac{3}{4}x^3y^3\)
\(=\frac{-3}{2}x^3y^3+\frac{3}{4}x^3y^3=\frac{-3}{4}x^3y^3\)
9.
\(\frac{1}{7}x^2y^3(\frac{-14}{3}xy^2)-\frac{1}{2}xy(x^2y^4)\)
\(=(\frac{1}{7}.\frac{-14}{3})(x^2.x)(y^3.y^2)-\frac{1}{2}(x.x^2)(y.y^4)\)
\(=\frac{-2}{3}x^3y^5-\frac{1}{2}x^3y^5=-\frac{7}{6}x^3y^5\)
10.
\(\frac{2}{5}x^4y^5(\frac{5}{4}x^2y^3)+\frac{5}{3}x^2y^3(-\frac{9}{10}x^4y^5)\)
\(=(\frac{2}{5}.\frac{5}{4})(x^4.x^2)(y^5.y^3)+(\frac{5}{3}.\frac{-9}{10})(x^2.x^4)(y^3.y^5)\)
\(=\frac{1}{2}x^6y^8-\frac{3}{2}x^6y^8=-x^6y^8\)
