Question

помогите пожалуйста срочно

Answer 1

$1)\frac{5a-6ab}{ab-2b^{2}}+\frac{10b-12b^{2} }{2b^{2}-ab}=\frac{5a-6ab}{ab-2b^{2}} -\frac{10b-12b^{2}}{ab-2b^{2}}= \frac{5a-6ab-10b+12b^{2}}{ab-2b^{2}}=\\\\=\frac{(12b^{2}-6ab)-(10b-5a) }{b(a-2b)}=\frac{6b(2b-a)-5(2b-a)}{b(a-2b)}=\frac{(2b-a)(6b-5)}{b(a-2b)}=\frac{5-6b}{b}\\\\b=500\Rightarrow \frac{5-6b}{b}=\frac{5-6*500}{500}=\frac{5-3000}{500} =-5,99$

$2)\frac{x^{4} -3x^{3}+6x^{2}-27x}{9x^{2}}=\frac{(x^{4}-27x)-(3x^{3}-6x^{2})}{9x^{2}}=\frac{x(x^{3}-27)-3x^{2}(x-2)}{9x^{2}}=\\\\=\frac{x(x^{3}-27)}{9x^{2}}-\frac{3x^{2}(x-2)}{9x^{2}}=\frac{x^{3}-27 }{9x}-\frac{x-2}{3}$