Giúp mk mấy câu này với!
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Lần sau bạn đăng riêng ra nhé
1/
a/ \(\lim\limits_{x\rightarrow2}\dfrac{2^2-4.2-2}{\sqrt{2+7}-5}=3\)
b/ \(\lim\limits_{x\rightarrow2}\dfrac{2\left(x-2\right)\left(x-\dfrac{1}{2}\right)\left(\sqrt{3x-2}+2\right)}{3\left(x-2\right)}=\dfrac{2\left(2-\dfrac{1}{2}\right)\left(\sqrt{3.2-2}+2\right)}{3}=...\)
c/ \(\lim\limits_{x\rightarrow-\infty}\dfrac{-\dfrac{3x}{x}+\dfrac{1}{x}}{-\sqrt{\dfrac{4x^2}{x^2}-\dfrac{3x}{x^2}+\dfrac{1}{x^2}}+\dfrac{x}{x}}=\dfrac{-3}{-2+1}=3\)
2/
\(\lim\limits_{x\rightarrow-1^+}f\left(x\right)=\lim\limits_{x\rightarrow-1^+}\dfrac{2x^2+5x+3}{x+1}=\lim\limits_{x\rightarrow-1^+}\dfrac{2\left(x+1\right)\left(x+\dfrac{3}{2}\right)}{x+1}=1=\lim\limits_{x\rightarrow-1^-}f\left(x\right)\)
\(f\left(x\right)=3.2021+4=...\)
\(\lim\limits_{x\rightarrow1}f\left(x\right)\ne f\left(x\right)\) => ham so gian doan tai x=-1
b/ \(f\left(x\right)=\lim\limits_{x\rightarrow-1}f\left(x\right)\Leftrightarrow3m+4=1\Leftrightarrow m=-1\)
3/ Kia là -ax-b hay cộng nhỉ?
1 send - will receive
2 do - will improve
3 find - will give
4 will go - has
5 will go- gets
6 doesn't phone - will leave
7 don't study - won't pass
8 rains - won't have to
9 won't be able - watch
10 can't move - isn't
11 study - will pass
23. Please take the form from your teacher and ask her to sign.
24. Can you show me the nearest way to the post office
25. We are going to plant the flowers in the parks and water them in the afternoon.
26. My brother is very good at repairing household appliances.
a) \(D=\left(\dfrac{2}{x+2}-\dfrac{4}{x^2+4x+4}\right):\left(\dfrac{2}{x^2-4}+\dfrac{1}{2-x}\right)\)\(=\left(\dfrac{2}{x+2}-\dfrac{4}{\left(x+2\right)^2}\right):\left(\dfrac{2}{\left(x-2\right)\left(x+2\right)}-\dfrac{1}{x-2}\right)\)
\(=\left(\dfrac{2\left(x+2\right)}{\left(x+2\right)^2}-\dfrac{4}{\left(x+2\right)^2}\right):\left(\dfrac{2}{\left(x-2\right)\left(x+2\right)}-\dfrac{x+2}{\left(x-2\right)\left(x+2\right)}\right)\)
\(=\dfrac{2\left(x+2\right)-4}{\left(x+2\right)^2}:\dfrac{2-x-2}{\left(x-2\right)\left(x+2\right)}\)
\(=\dfrac{2x+4-4}{\left(x+2\right)^2}:\dfrac{-x}{\left(x-2\right)\left(x+2\right)}\)
\(=\dfrac{2x}{\left(x+2\right)^2}.\dfrac{\left(x-2\right)\left(x+2\right)}{-x}\)
\(=\dfrac{-2.\left(x-2\right)}{x+2}\)
\(x^2-5x+6=0\\ \Rightarrow\left(x^2-2x\right)-\left(3x-6\right)=0\\ \Rightarrow\left(x-2\right)\left(x-3\right)=0\\ \Rightarrow\left[{}\begin{matrix}x-2=0\\x-3=0\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=2\\x=3\end{matrix}\right.\)
\(P=\dfrac{-2.\left(x-2\right)}{x+2}\)
Thay \(x=2\), ta có:
\(P=\dfrac{-2.\left(2-2\right)}{2+2}\)
\(=0\)
Thay \(x=3\), ta có:
\(P=\dfrac{-2.\left(3-2\right)}{3+2}\)
\(=-\dfrac{2}{5}\)
Em tham khảo thử nha:
Cách mạng tư sản pháp đã trải qua 2 giai đoạn phát triển:
– Giai đoạn 1 : Chế độ quân chủ lập hiến ( 14/7/1789 – 10/8/1792)
– Giai đoạn 2 : Chuyên chính dân chủ cách mạng Gia cô banh (2/6/1793 – 27/7/1794)
2d
3b
4b
5d
Thi ko giúp