Question

Решите : a^2-4b^2/2ab:(1/2b-1/a)=
При a=2 15/19 b= 5 2/19

Answer 1

$\frac{ a^{2} - 4b^{2} }{2ab} : ( \frac{1}{2b} - \frac{1}{a})= \frac{(a-2b)(a+2b)}{2ab} : \frac{a-2b}{2ab}= \frac{(a-2b)(a+2b)*2ab}{2ab*(a-2b)}=a+2b$

Если $a= 2\frac{15}{19} , b= 5\frac{2}{19}$ , то

$2 \frac{15}{19}+2*5 \frac{2}{19} = 2 \frac{15}{19} + \frac{2*97}{19} = 2\frac{15}{19} +10\frac{4}{19} =13$