Giúp e bài này vớiiiii
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
b: \(\dfrac{A}{B}=\dfrac{-x^3+5x^2-x-8x^2+40x-8+2}{x^2-5x+1}\)
\(=-x-8+\dfrac{2}{x^2-5x+1}\)
Can children and their parents be good friends? Yes of course, I encourage that. If a child and parent be friends and still have boundaries about there has to be respect, and there are still rules, but can have friendship and fun and that builds trust. That can be the most beautiful relationship.
Hơi ngắn
Bài 6:
PTHH: \(Fe+2HCl\rightarrow FeCl_2+H_2\uparrow\)
a_____2a______a_____a (mol)
\(2Al+6HCl\rightarrow2AlCl_3+3H_2\uparrow\)
b______3b______b_____\(\dfrac{3}{2}\)b (mol)
Ta lập được HPT: \(\left\{{}\begin{matrix}56a+27b=22,2\\a+\dfrac{3}{2}b=\dfrac{13,44}{22,4}=0,6\end{matrix}\right.\) \(\Leftrightarrow\left\{{}\begin{matrix}a=0,3\\b=0,2\end{matrix}\right.\)
\(\Rightarrow\left\{{}\begin{matrix}\%m_{Fe}=\dfrac{0,3\cdot56}{22,2}\cdot100\%\approx75,68\%\\\%m_{Al}=24,32\%\end{matrix}\right.\)