Question

Срочно помогите пожалуйста ​

Answer 1

$1)\frac{5y^{2}-20y+20 }{y^{3}-1 }*\frac{3y^{2}+3y+3}{10y-20}=\frac{5(y^{2}-4y+4)*3(y^{2}+y+1)}{(y-1)(y^{2}+y+1)*10(y-2)}=\frac{3*(y-2)^{2}}{2*(y-1)(y-2)}=\\\\=\frac{3(y-2)}{2(y-1)}=\frac{3y-6}{2y-2} \\\\\\2)\frac{a^{2}-4b^{2}}{9a^{2}-b^{2}}:\frac{a^{2}+4ab+4b^{2}}{9a^{2}-6ab+b^{2}}=\frac{(a-2b)(a+2b)}{(3a-b)(3a+b)}*\frac{(3a-b)^{2}}{(a+2b)^{2}}=\frac{(a-2b)(3a-b)}{(3a+b)(a+2b)}$