Question

Выражения 1)3/у+5-2/у-5+30/у^2-25 2)1/(а-3)^2-2/а^2-9+1/(а+3)^2 3)1/х+3-10х+3/х^3+27+х+4/х^2-3х+9

Answer 1

$\frac{3}{y} +5- \frac{2}{y} -5+ \frac{30}{y^2}-25= \frac{1}{y}+ \frac{30}{y^2}-25= \frac{y+30-25y^2}{y^2}$

$\frac{1}{(a-3)^2}- \frac{2}{a^2} -9+ \frac{1}{(a+3)^2} = \\\ = \frac{a^2(a+3)^2-2(a+3)^2(a-3)^2-9a^2(a+3)^2(a-3)^2+a^2(a-3)^2}{a^2(a+3)^2(a-3)^2} \\\ = -\frac{9a^6+513a^2+162}{a^2(a+3)^2(a-3)^2}$

$\frac{1}{x} +3-10x+ \frac{3}{x^3}+27+x+ \frac{4}{x^2} -3x+9= \\\ = \frac{1}{x} +39-12x+ \frac{3}{x^3}+ \frac{4}{x^2} = \\\ = \frac{x^2+39x^3-12x^4+3+4x}{x^3}$