Tìm x thuộc Q, biết:
a) (x-4).(x+1/3)>0
b) x+1/1974 + x+2/1973 + x+3/1974 = -3
Những câu hỏi liên quan
Tìm x, biết\(\frac{x+1}{1974}+\frac{x+2}{1973}+\frac{x+3}{1972}=-3\)
\(\frac{x+1}{1974}+1+\frac{x+2}{1973}+1+\frac{x+3}{1972}+1=-3+3\)
\(\Leftrightarrow\frac{x+1975}{1974}+\frac{x+1975}{1973}+\frac{x+1975}{1972}=0\)
\(\Leftrightarrow\left(x+1975\right)\left(\frac{1}{1974}+\frac{1}{1973}+\frac{1}{1972}\right)=0\)
=> x + 1975 = 0. => x = -1975 ( vì 1/1974 + 1/1973 + 1/1972 khác 0 )
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Tim x biet: x+1/1974+x+2/1973+x+3/1972=-3
tim x biết (x+1) /1974 + (x+2) / 1973 + (x+3) / 1972=-3
Tìm x:
\(\frac{x+1}{1974}+\frac{x+2}{1973}+\frac{x+3}{1972}=-3\)
\(\frac{x+1}{1974}+\frac{x+2}{1973}+\frac{x+3}{1972}=-3\)
\(=>\left(\frac{x+1}{1974}+1\right)+\left(\frac{x+2}{1973}+1\right)+\left(\frac{x+3}{1972}+1\right)=-3+3\)
\(=>\frac{x+1975}{1974}+\frac{x+1975}{1973}+\frac{x+1975}{1972}=0\)
\(\left(x+1975\right)\left(\frac{1}{1974}+\frac{1}{1973}+\frac{1}{1972}\right)=0\)
\(=>x+1975=0=>x=-1975\)
Vậy \(x=-1975\)
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\(\frac{x+1}{1974}+\frac{x+2}{1973}+\frac{x+3}{1972}=-3\)
\(\Leftrightarrow\left(\frac{x+1}{1974}+1\right)+\left(\frac{x+2}{1973}+1\right)+\left(\frac{x+3}{1972}+1\right)=0\)
\(\Leftrightarrow\frac{x+1975}{1974}+\frac{x+1975}{1973}+\frac{x+1975}{1972}=0\)
\(\Leftrightarrow\left(x+1975\right)\left(\frac{1}{1974}+\frac{1}{1973}+\frac{1}{1972}\right)=0\)
\(\Leftrightarrow x+1975=0\)
\(\Leftrightarrow x=-1975\)
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\(\frac{x+1}{1974}+\frac{x+2}{1973}+\frac{x+3}{1972}=-3\)
\(\left(\frac{x+1}{1974}+1\right)+\left(\frac{x+2}{1973}+1\right)+\left(\frac{x+3}{1972}+1\right)=0\)
\(\left(\frac{x+1}{1974}+\frac{1974}{1974}\right)+\left(\frac{x+2}{1973}+\frac{1973}{1973}\right)+\left(\frac{x+3}{1972}+\frac{1972}{1972}\right)=0\)
\(\frac{x+1+1974}{1974}+\frac{x+2+1973}{1973}+\frac{x+3+1972}{1972}=0\)
\(\frac{x+1975}{1974}+\frac{x+1975}{1973}+\frac{x+1975}{1972}=0\)
\(\left(x+1975\right):\left(\frac{1}{1974}+\frac{1}{1973}+\frac{1}{1972}\right)=0\)
=>\(x+1975=0\)(vì 1/1974+1/1973+1/1972 khác 0)
=>\(x=-1975\)
Chúc bạn học tốt!
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\(\frac{x+1}{1974}+\frac{x+2}{1973}+\frac{x+3}{1972}=-3\)
\(\frac{x+5}{2005}+\frac{x+6}{2004}+\frac{x+7}{2003}=-3\)
TÌM X
\(\frac{x+1}{1974}+\frac{x+2}{1973}+\frac{x+3}{1972}=-3\)
\(\Rightarrow\left(\frac{x+1}{1974}+1\right)+\left(\frac{x+2}{1973}+1\right)+\left(\frac{x+3}{1972}+1\right)=0\)
\(\Rightarrow\frac{x+1+1974}{1974}+\frac{x+2+1973}{1973}+\frac{x+3+1972}{1972}=0\)
\(\Rightarrow\frac{x+1975}{1974}+\frac{x+1975}{1973}+\frac{x+1975}{1972}=0\)
\(\Rightarrow\left(x+1975\right)\frac{1}{1974}+\frac{1}{1973}+\frac{1}{1972}=0\)
Mà \(\frac{1}{1974}+\frac{1}{1973}+\frac{1}{1972}\ne0\)
\(\Rightarrow x+1975=0\)
\(\Rightarrow x=0+1975\)
\(\Rightarrow x=1975\)
Vậy \(x=1975\)
b) phần này làm tương tự phần a nha, chuyển -3 sang vế bên trái r cộng từng p.số vs 1 và sau đó nhóm tử số chung ra ngoài ^^
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Tìm x biết:
a) x(x-3)+2x-6=0
b) (x+1)2-4(x+1)=0
c) (2x+5)(4x+3)-8x(x+3)=10
a: \(x\left(x-3\right)+2x-6=0\)
\(\Leftrightarrow\left(x-3\right)\left(x+2\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=3\\x=-2\end{matrix}\right.\)
b: \(\left(x+1\right)^2-4\left(x+1\right)=0\)
\(\Leftrightarrow\left(x+1\right)\left(x-3\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=-1\\x=3\end{matrix}\right.\)
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13 tháng 9 2021 lúc 17:12
bài 3: tìm x , biết:
a)(x+3).(2x-1)-(x-3).(x+1)=0
b)(x+4).(2x-3)-3.(x-2).(x+2)=0
c)x.(x-5).(x+5)-(x+2).(x2-2x+4)=17
a) \(\left(x+3\right)\left(2x-1\right)-\left(x-3\right)\left(x+1\right)=0\)
\(\Leftrightarrow2x^2+5x-3-x^2+2x+3=0\)
\(\Leftrightarrow x^2+7x=0\Leftrightarrow x\left(x+7\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x=-7\end{matrix}\right.\)
b) \(\left(x+4\right)\left(2x-3\right)-3\left(x-2\right)\left(x+2\right)=0\)
\(\Leftrightarrow2x^2+5x-12-3x^2+12=0\)
\(\Leftrightarrow x^2-5x=0\Leftrightarrow x\left(x-5\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x=5\end{matrix}\right.\)
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Tìm x,biết:
a)5x.(x+1)-5.(x+1).(x-2)=0
b)(4x+1).(x-2)-(2x-3)2=4
a)5(x+1)(x-x-2)=0
=>5(x+1).-2=0
=>5(x+1)=0
=>x+1=0
=>x=-1
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a)5x.(x+1)-5.(x+1).(x-2)=0
⇒5x(x+1)-(5x-10)(x+1)=0
⇒(x+1)(5x-5x+10)=0
⇒10(x+1)=0
⇒x+1=0⇒x=-1
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a) \(5x\left(x+1\right)-5\left(x+1\right)\left(x-2\right)=0\)
\(\Leftrightarrow5\left(x+1\right)\left(x-x+2\right)=0\)
\(\Leftrightarrow10\left(x+1\right)=0\)
\(\Leftrightarrow x+1=0\Leftrightarrow x=-1\)
b) \(\left(4x+1\right)\left(x-2\right)-\left(2x-3\right)^2=4\)
\(\Leftrightarrow4x^2-7x-2-4x^2+12x-9=4\)
\(\Leftrightarrow5x=15\Leftrightarrow x=3\)
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Xem thêm câu trả lời
giải phương trình(tiếp)
frac{5}{3x+2}2x-1
frac{x-45}{55}+frac{x-47}{53}frac{x-55}{45}+frac{x-53}{47}
frac{2-x}{2002}-1frac{1-x}{2003}-frac{x}{2004}
frac{x^2-10x-29}{1971}+frac{x^2-10x-27}{1973}frac{x^2-10x-1971}{29}+frac{x^2-10x-1973}{27}
frac{201-x}{99}+frac{203-x}{97}frac{205-x}{95}+3
frac{2x-frac{4-3x}{5}}{15}frac{7x-frac{x-3}{2}}{5}-x+1
frac{frac{1}{2}+a}{a-frac{1}{2}}-frac{frac{1}{2}-a}{a+frac{1}{2}}frac{aleft(3a+1right)}{a^2-left(frac{1}{2}right)^2}
frac{x-29}{1970}+frac{x-27}{1972...
Đọc tiếp
giải phương trình(tiếp)
\(\frac{5}{3x+2}=2x-1\)
\(\frac{x-45}{55}+\frac{x-47}{53}=\frac{x-55}{45}+\frac{x-53}{47}\)
\(\frac{2-x}{2002}-1=\frac{1-x}{2003}-\frac{x}{2004}\)
\(\frac{x^2-10x-29}{1971}+\frac{x^2-10x-27}{1973}=\frac{x^2-10x-1971}{29}+\frac{x^2-10x-1973}{27}\)
\(\frac{201-x}{99}+\frac{203-x}{97}=\frac{205-x}{95}+3\)
\(\frac{2x-\frac{4-3x}{5}}{15}=\frac{7x-\frac{x-3}{2}}{5}-x+1\)
\(\frac{\frac{1}{2}+a}{a-\frac{1}{2}}-\frac{\frac{1}{2}-a}{a+\frac{1}{2}}=\frac{a\left(3a+1\right)}{a^2-\left(\frac{1}{2}\right)^2}\)
\(\frac{x-29}{1970}+\frac{x-27}{1972}+\frac{x-25}{1974}+\frac{x-23}{1976}+\frac{x-21}{1978}+\frac{x-19}{1980}=\frac{x-1970}{29}+\frac{x-1972}{27}+\frac{x-1974}{25}+\frac{x-1976}{23}+\frac{x-1978}{21}+\frac{x-1978}{21}+\frac{x-1980}{19}\)