Question

1/7х + 1/х
2а/а-4 - 5а-2/16-а²
сложите и вычеслите​

Answer 1

$1) \frac{1}{7x} +\frac{1}{x}=\frac{1+7}{7x}=\frac{8}{7x}\\2) \frac{2a}{a-4}-\frac{5a-2}{16-a^{2} }=\frac{2a}{a-4} -\frac{5a-2}{(4-a)(4+a)}=\frac{2a}{a-4}+\frac{5a-2}{(a-4)(a+4)}=\frac{2a^{2} +8a+5a-2}{(a-4)(a+4)}=\frac{2a^{2} +13a-2}{16-a^{2}}$