Question

СРОЧНО В ПРИЛОЖЕНИИ ЗАДАНИЕ!!!!!!!!!!!НУЖЕН ПОЛНЫЙ РАСПИСАНЫЙ ОТВЕТ!!!!!!!!!!!!!!!!!!!!!!!!ПОЖАЛУЙСТА!!!!!!!!!!!!!!!!!!!!!!!!!!!!ДАЮ 20 БАЛОВ!!!!!!!!!!!!!!!!!

Answer 1

Объяснение:

$1)\\\frac{1}{\sqrt{b}-5 }-\frac{\sqrt{b} }{b-25} =\frac{1}{\sqrt{b}-5 }-\frac{\sqrt{b} }{(\sqrt{b}+5)(\sqrt{b}-5) } =\frac{\sqrt{b}+5-\sqrt{b} }{(\sqrt{b}+5)(\sqrt{b}-5) }=\frac{5}{(\sqrt{b}+5)(\sqrt{b}-5) }.\\2)\\ \frac{5}{(\sqrt{b}+5)(\sqrt{b}-5)}:\frac{5\sqrt{b} }{b-10\sqrt{b}+25 } = \frac{5}{(\sqrt{b}+5)(\sqrt{b}-5)}*\frac{(\sqrt{b}-5)^2 }{5\sqrt{b} }= \frac{\sqrt{b}-5 }{\sqrt{b}*(\sqrt{b}+5) }.$

$3)\\\frac{\sqrt{b}-5 }{\sqrt{b}*(\sqrt{b}+5) } -\frac{2}{\sqrt{b}+5 }=\frac{\sqrt{b}-5-2\sqrt{b} }{\sqrt{b}*(\sqrt{b}+5) }=\frac{-\sqrt{b}-5 }{\sqrt{b}*(\sqrt{b}+5) } =\frac{-(\sqrt{b}+5) }{\sqrt{b}*(\sqrt{b}+5) } =-\frac{1}{\sqrt{b} }=\\=-\frac{1}{\sqrt{\frac{16}{49} } }=-\sqrt{\frac{49}{16} }=-\frac{7}{4}=-1,75.$