HOC24
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\(A=\frac{\sqrt{x}-2+3}{\sqrt{x}-2}=1+\frac{3}{\sqrt{x}-2}\)
A nguyên khi \(\frac{3}{\sqrt{x}-2}\) nguyên
<=> \(\sqrt{x}+2\) là ước của 3
\(\Leftrightarrow\sqrt{x}+2\in\left\{1;3;-1;-3\right\}\)
\(\Leftrightarrow\sqrt{x}\in\left\{-1;1;-3;-5\right\}\)
\(\Leftrightarrow x\in\left\{1;2;9;25\right\}\)
Vậy x=1 ; x= 9 ; x=25
My stomachache _____disappeared______ after I took the tablets. APPEAR
It was _____unkindly______ of you not to help him when he was in trouble. KIND
When my father has free time he often tells us____funny___ stories. FUN
Look! the children are eating_____hungrily_____. HUNGRY
It's a nice shop and the assistants are all polite and very __helpfull___. HELP
Catching the common cold is ____unpleasant___ for everybody. PLEASE
Do you know a good ____decorater__ to decorate my house? DECORATE
TT
cô on mà dc có 1 cái
Số 809 chia 11 dư 6 chia 4 dư 1 va 19 dư 11
\(\Rightarrow\left|x+\frac{11}{2}\right|>\frac{11}{2}\)
\(\Rightarrow\left[\begin{array}{nghiempt}-\left(x+\frac{11}{2}\right)>\frac{11}{2}\\x+\frac{11}{2}>\frac{11}{2}\end{array}\right.\)
\(\Rightarrow\left[\begin{array}{nghiempt}-x-\frac{11}{2}>\frac{11}{2}\\x>0\end{array}\right.\)
\(\Rightarrow\left[\begin{array}{nghiempt}x< 11\\x>0\end{array}\right.\)
Vaay x<11 ; x>0
\(\Rightarrow\left[\begin{array}{nghiempt}x-\frac{5}{3}< \frac{1}{3}\\-\left(x-\frac{5}{3}\right)< \frac{1}{3}\end{array}\right.\)
\(\Rightarrow\left[\begin{array}{nghiempt}x< 2\\-x+\frac{5}{3}< \frac{1}{3}\end{array}\right.\)
\(\Rightarrow\left[\begin{array}{nghiempt}x< 2\\-x< -\frac{4}{3}\end{array}\right.\)
\(\Rightarrow\left[\begin{array}{nghiempt}x< 2\\x>\frac{4}{3}\end{array}\right.\)
=> \(\frac{4}{3}< x< 2\)
Nửa chu vi hình chữ nhật là :
60 : 2 = 30 ( cm )
Chiều dài là :
(30 - 8 ) : 2 = 12 ( cm )
chiều rộng là :
30-12=18 ( cm )
Diện tích hình chữ nhật là :
18 x 12 = 216 ( cm2)
Đ/S 216 cm2
\(\left|3\right|< \left|5\right|\)
\(\left|-1\right|>\left|0\right|\)
\(\left|-3\right|< \left|-5\right|\)
\(\left|2\right|=\left|-2\right|\)
\(\Rightarrow\left(x+1\right)\left(x-3\right)=\left(x+3\right)\left(2x-3\right)\)
=> \(x^2-3x+x-3=2x^2-3x+6x-9\)
=> \(-3+9=2x^2-3x+6x-x^2+3x-x\)
=> \(x^2+5x=6\)
=> \(x\left(x+5\right)=6\)
THử với các ước của 6 ta được x=1
Vậy x=1