Question

Доказать тождество! Пожалуйста, очень срочно!!!

Answer 1

$\frac{2y}{y+3}+(y-3)^2\cdot (\frac{2}{9-6y+y^2}+\frac{1}{9-y^2})=\frac{2y}{y+3}+(y-3)^2\cdot (\frac{2}{(3-y)^2} +\frac{1}{(3-y)(3+y)})=\\\\\\=\frac{2y}{y+3}+(y-3)^2\cdot \frac{2(3+y)+(3-y)}{(3-y)^2(3+y)}=\frac{2y}{y+3}+(y-3)^2\cdot \frac{y+9}{(y-3)^2(3+y)}=\\\\\\=\frac{2y}{y+3}+\frac{y+9}{y+3}=\frac{3y+9}{y+3}=\frac{3(y+3)}{y+3}=3$

Answer 2

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