Question

пожалуйста, очень надо​

Answer 1

Ответ:

$1 + \frac{2a - 1}{a {}^{2} - 2a + 1} - \frac{a}{a - 1} = 1+\frac{2a-1}{\left(a-1\right)^{2}}-\frac{a}{a-1} =\frac{\left(a-1\right)^{2}}{\left(a-1\right)^{2}}+\frac{2a-1}{\left(a-1\right)^{2}}-\frac{a}{a-1} =\frac{\left(a-1\right)^{2}+2a-1}{\left(a-1\right)^{2}}-\frac{a}{a-1} =\frac{a^{2}-2a+1+2a-1}{\left(a-1\right)^{2}}-\frac{a}{a-1} =\frac{a^{2}}{\left(a-1\right)^{2}}-\frac{a}{a-1} =\frac{a^{2}}{\left(a-1\right)^{2}}-\frac{a\left(a-1\right)}{\left(a-1\right)^{2}} =\frac{a^{2}-a\left(a-1\right)}{\left(a-1\right)^{2}} =\frac{a^{2}-a^{2}+a}{\left(a-1\right)^{2}} =\frac{a}{\left(a-1\right)^{2}}$