a)=>x+1<0=>x<-1
x-2 =<0=> x=<2
b)x-2>0=>x>2
x+2/3>=0=>x>=-2/3
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Bài 3: Nhân, chia số hữu tỉ
Các câu hỏi tương tự
Tìm x
a, \(\left(2-x\right)\times\left(\dfrac{4}{5}-x\right)< 0\)
b, \(\left(x-\dfrac{3}{2}\right)\times\left(2\times x-1\right)>0\)
c, \(\left(x-\dfrac{4}{7}\right)\div\left(x+\dfrac{1}{2}\right)>0\)
d, \(\left(2\times x-5\right)\div\left(x+1\dfrac{3}{4}\right)< 0\)
Giúp mk với
Tìm \(x\in Q\), biết rằng :
a) \(\dfrac{11}{12}-\left(\dfrac{2}{5}+x\right)=\dfrac{2}{3}\)
b) \(2x\left(x-\dfrac{1}{7}\right)=0\)
c) \(\dfrac{3}{4}+\dfrac{1}{4}:x=\dfrac{2}{5}\)
Câu 1: Tim x, y biet:
a) 2.x-dfrac{5}{4}dfrac{20}{15}
b) left(x+dfrac{1}{3}right)^3left(dfrac{-1}{8}right)
Câu 2: Tim cac so a,b biet:
dfrac{a}{2}dfrac{b}{3} va a+b-15
Câu 3: Tim x in Q biet:
left(x+1right)left(x-2right) 0
Câu 4: Thuc hien phep tinh:
Bleft(dfrac{3}{7}right)^{21}:left(dfrac{9}{49}right)^9
Đọc tiếp
Câu 1: Tim x, y biet:
a) \(2.x-\dfrac{5}{4}=\dfrac{20}{15}\)
b) \(\left(x+\dfrac{1}{3}\right)^3=\left(\dfrac{-1}{8}\right)\)
Câu 2: Tim cac so a,b biet:
\(\dfrac{a}{2}=\dfrac{b}{3}\) va \(a+b=-15\)
Câu 3: Tim x \(\in\) Q biet:
\(\left(x+1\right)\left(x-2\right)< 0\)
Câu 4: Thuc hien phep tinh:
\(B=\left(\dfrac{3}{7}\right)^{21}:\left(\dfrac{9}{49}\right)^9\)
Tìm \(x\in Q\), biết rằng:
a) \(\dfrac{11}{12}-\left(\dfrac{2}{5}+x\right)=\dfrac{2}{3}\)
b) \(2x.\left(x-\dfrac{1}{7}\right)=0\)
c) \(\dfrac{3}{4}+\dfrac{1}{4}:x=\dfrac{2}{5}\)
Bài 1, Tìm x biết
a)\(\left|x\right|+\left|x+2\right|=0\)
b)\(\left|x\left(x^2-\frac{5}{4}\right)\right|=x\)
Tìm x ạ
b) \(\left|\dfrac{3}{4}x-\dfrac{3}{4}\right|-\dfrac{3}{4}=\left|\dfrac{-3}{4}\right|\)
c) \(\left|x+\dfrac{3}{5}\right|-\left|x-\dfrac{7}{3}\right|=0\)
Tìm x:
\(\dfrac{3}{\left(x+2\right)\left(x+5\right)}\)\(+\dfrac{5}{\left(x+5\right)\left(x+10\right)}\)\(+\dfrac{7}{\left(x+10\right)\left(x+17\right)}\)\(=\dfrac{x}{\left(x+2\right)\left(x+17\right)}\)
Tìm x biết
\(\left|2x-1\right|\)=2x
\(\left|x-3\right|-\left|4-x\right|=0\)
\(\left|x\right|+\left|x-2\right|=2\)
tìm GTNN của A=\(\left|x-5\right|+\left|x-2\right|\)
mk cần gấp ( lm đc câu nào thì giúp mk . mk tick cho )
a) Cho x3,7. So sánh:
A [x] + [x+dfrac{1}{5}] + [x+dfrac{2}{5}] + [x+dfrac{3}{5}] + [x+dfrac{4}{5}] và B[5x]
b)Tính [dfrac{100}{3}] + [dfrac{100}{3^2}] + [dfrac{100}{3^3}] + [dfrac{100}{3^4}]
c) Tính left[dfrac{50}{2}right]+left[dfrac{50}{2^2}right]+left[dfrac{50}{2^3}right]+left[dfrac{50}{2^4}right]+left[dfrac{50}{2^5}right]
Đọc tiếp
a) Cho x=3,7. So sánh:
A = [x] + [x+\(\dfrac{1}{5}\)] + [x+\(\dfrac{2}{5}\)] + [x+\(\dfrac{3}{5}\)] + [x+\(\dfrac{4}{5}\)] và B=[5x]
b)Tính [\(\dfrac{100}{3}\)] + [\(\dfrac{100}{3^2}\)] + [\(\dfrac{100}{3^3}\)] + [\(\dfrac{100}{3^4}\)]
c) Tính \(\left[\dfrac{50}{2}\right]+\left[\dfrac{50}{2^2}\right]+\left[\dfrac{50}{2^3}\right]+\left[\dfrac{50}{2^4}\right]+\left[\dfrac{50}{2^5}\right]\)