Question

срочно спростіть вираз даю 50 балов​

Answer 1

$1)\frac{a}{a^{2}-10a+25 }+\frac{a+2}{25-a^{2}} =\frac{a}{(5-a)^{2}}+\frac{a+2}{(5-a)(5+a)}=\frac{a*(5+a)+(a+2)*(5-a)}{(5-a)^{2}(5+a)} =\\\\=\frac{5a+a^{2}+5a-a^{2}+10-2a}{(5-a)^{2}(5+a)} =\frac{8a+10}{(5-a)^{2}(5+a)}\\\\\\2)\frac{y+3}{2y+2}-\frac{y+1}{2y-2}+\frac{3}{y^{2} -1}=\frac{y+3}{2(y+1)}-\frac{y+1}{2(y-1)}+\frac{3}{(y -1)(y+1)}=\frac{(y+3)(y-1)-(y+1)(y+1)+3*2}{2(y -1)(y+1)}=\\\\=\frac{y^{2}-y+3y-3-y^{2}-2y-1+6}{2(y -1)(y+1)}=\frac{2}{2(y -1)(y+1)}=\frac{1}{y^{2}-1}$