Question

Помогите пожалуйста 2.45 очень нужно!!!

Answer 1

Объяснение:

$1)\\(5x^4+3x^4-6x^4)+(3x^3y-8x^3y+x^3y)+(-2x^2y^2+9x^2y^2+5x^2y^2)+\\+(-4xy^3+xy^3-9xy^3)=2x^4-4x^3y+12x^2y^2-12xy^3.$

$2)\\(-\frac{5}{6}a^2+\frac{5}{12}a^2+2\frac{1}{2}a^2)+(4\frac{2}{3}ab-\frac{4}{3}ab+\frac{5}{4}ab)+(\frac{3}{4}b^2 -\frac{7}{4}b^2-b^2)=\\= (-\frac{5}{6}a^2+\frac{5}{12}a^2+\frac{5}{2}a^2)+(\frac{14}{3}ab-\frac{4}{3}ab+\frac{5}{4}ab)+(\frac{3}{4}b^2 -\frac{7}{4}b^2-b^2)=\\=\frac{-5*2a^2+5a^2+5*6a^2}{12} +\frac{14*4ab-4*4ab+5*3ab}{12} +\frac{3b^2-7b^2-4b^2}{4} =\\=\frac{-10a^2+5a^2+30a^2}{12} +\frac{64ab-16ab+15ab}{12} +\frac{-8b^2*3}{4*3} =\frac{25a^2}{12}+\frac{63ab}{12}-\frac{24b^2}{12}=$

$=\frac{25a^2+63ab-24b^2}{12} .$

$3)\\(5\frac{1}{4} m^3-5\frac{5}{6} m^3)+(2\frac{1}{6}m^2n+13m^2n)+(3\frac{1}{2}mn^2-1\frac{1}{4}mn^2)+(-8\frac{2}{3}n^3+ n^3 )=\\=(\frac{21}{4}m^3-\frac{35}{6} m^3)+(\frac{13}{6}m^2n+13m^2n)+(\frac{7}{2} mn^2-\frac{5}{4}mn^2)+(-\frac{26}{3}n^3+n^3)=\\=\frac{21m^3-35*2m^3}{12} +\frac{13m^2n+6*13m^2n}{6} +\frac{7*2mn^2-5mn^2}{4}+\frac{-26n^3+3n^3}{3} =\\=\frac{21m^3-70m^3}{12} +\frac{13m^2n +78m^2n}{6} +\frac{14mn^2-5mn^2}{4} +\frac{-23n^3}{3}=$

$=-\frac{49}{12}m^3+\frac{91}{6} m^2n+\frac{9}{4}mn^2-\frac{23}{3}n^3.$