Question

Упростите выражение и найдите его значение:

Answer 1

Объяснение:

$\frac{a+4}{a^2-10a+25}-\frac{a+2}{a^2-25} =\frac{a+4}{(a-5)^2}-\frac{a+2}{(a-5)*(a+5)}=\frac{(a+4)*(a+5)-(a+2)*(a-5)}{(a-5)^2*(a+5)} =\\=\frac{a^2+9a+20-(a^2-3a-10)}{(a-5)^2*(a+5)}=\frac{a^2+9a+20-a^2+3a+10}{(a-5)^2*(a+5)} =\frac{12a+30}{(a-5)^2*(a+5)}=\\=\frac{6*(x+5)}{(a-5)^2*(a+5)}=\frac{6}{(a-5)^2}= \frac{6}{(7,5-5)^2}=\frac{6}{2,5^2}=\frac{6}{6,25}=0,96.$