Violympic toán 8
Các câu hỏi tương tự
tìm GTNN
A=\(\dfrac{3x^2-2x+3}{x^2+1}\)
B=\(\dfrac{x^2-2011}{4\left(x^2+1\right)}\)
C=\(\dfrac{3x^2-8x+13}{x^2+5}\)
tìm GTNN
A=\(\dfrac{3x^2-2x+3}{x^2+1}\)
B=\(\dfrac{x^2-2011}{4\left(x^2+1\right)}\)
C=\(\dfrac{3x^2-8x+13}{x^2+5}\)
ai giúp mk với
Giải các phương trình sau:
1. \(a,\dfrac{6}{x-1}-\dfrac{4}{x-3}=\dfrac{8}{2x-6}\)
\(b,\dfrac{1}{x-2}+\dfrac{5}{x+1}=\dfrac{3}{2-x}\)
\(c,\dfrac{3x}{x-2}-\dfrac{x}{x-5}=\dfrac{3x}{\left(x-2\right)\left(5-x\right)}\)
2. \(a,\left(x+2\right)\left(3-4x\right)=x^2+4x+4\)
\(b,2x^2-6x+1\)
Bài 1: Giải phương trình
\(a,\dfrac{x+1}{2009}+\dfrac{x+3}{2007}=\dfrac{x+5}{2005}+\dfrac{x+7}{1993}\)
\(b,\left(x+2\right)^4+\left(x+4\right)^4=14\)
\(c,\left(x-3\right)\left(x-2\right)x+1=60\)
d, \(2x^4+3x^3-x^2+3x+2=0\)
Bài 1:cho phương trình
a,left(x-1right)^3-xleft(x-1right)^25xleft(2-xright)-11left(x+2right)
b,dfrac{left(x+10right)left(x+4right)}{12}-dfrac{left(x+4right)left(2-xright)}{4}dfrac{left(x+10right)left(x-2right)}{3}
c,dfrac{2left(x-3right)}{7}+dfrac{x-5}{3}dfrac{13x+4}{21}
d,dfrac{2x-1}{5}-dfrac{x-2}{3}dfrac{x+7}{5}
e,left(x-2right)^3+left(3x-1right)left(3x+1right)left(x+1right)^3
Đọc tiếp
Bài 1:cho phương trình
a,\(\left(x-1\right)^3-x\left(x-1\right)^2=5x\left(2-x\right)-11\left(x+2\right)\)
b,\(\dfrac{\left(x+10\right)\left(x+4\right)}{12}-\dfrac{\left(x+4\right)\left(2-x\right)}{4}=\dfrac{\left(x+10\right)\left(x-2\right)}{3}\)
c,\(\dfrac{2\left(x-3\right)}{7}+\dfrac{x-5}{3}=\dfrac{13x+4}{21}\)
d,\(\dfrac{2x-1}{5}-\dfrac{x-2}{3}=\dfrac{x+7}{5}\)
e,\(\left(x-2\right)^3+\left(3x-1\right)\left(3x+1\right)=\left(x+1\right)^3\)
Giải bất phương trình sau:
a) 3.(4x + 1 ) -2x (5x+2) 8x - 2
b) (4x2 -19x + 5 -2x - 3)2 0
c) x + 1 - dfrac{x-1}{3} dfrac{2x+3}{2}+dfrac{x}{3}+5
d) dfrac{left(3x-2right)^2}{3}-dfrac{left(2x+1right)^2}{3} xleft(x+1right)
e) 1- x .( 2x+1) 0
g) dfrac{4-x}{3x+5}ge0
h) dfrac{x+5}{x+7}-10
Mình cần gấp các bạn giúp mình với ạ. Mình cảm ơn nhiều lắm
Đọc tiếp
Giải bất phương trình sau:
a) 3.(4x + 1 ) -2x (5x+2) > 8x - 2
b) (4x2 -19x + 5 -2x - 3)2 > 0
c) x + 1 - \(\dfrac{x-1}{3}< \dfrac{2x+3}{2}+\dfrac{x}{3}+5\)
d) \(\dfrac{\left(3x-2\right)^2}{3}-\dfrac{\left(2x+1\right)^2}{3}< x\left(x+1\right)\)
e) 1- x .( 2x+1) = 0
g) \(\dfrac{4-x}{3x+5}\ge0\)
h) \(\dfrac{x+5}{x+7}-1>0\)
Mình cần gấp các bạn giúp mình với ạ. Mình cảm ơn nhiều lắm
4.Giải phương trình
a) dfrac{x+5}{x-5}-dfrac{x-5}{x+5}dfrac{20}{x^2-25}
b)dfrac{1}{x-1}+dfrac{2}{x+1}dfrac{x}{x^2-1}
c)5+dfrac{76}{x^2-16}dfrac{2x-1}{x+4}-dfrac{3x-1}{4-x}
d)dfrac{90}{x}-dfrac{36}{x-6}2
e)dfrac{1}{x}+dfrac{1}{x+10}dfrac{1}{12}
f)dfrac{x+3}{x-3}-dfrac{1}{x}dfrac{3}{xleft(x-3right)}
g)dfrac{3}{x+2}-dfrac{2}{x-2}+dfrac{8}{x^2-4}0
h)dfrac{3}{x+2}-dfrac{2}{x-3}dfrac{8}{left(x-3right)left(x+2right)}
i)dfrac{x}{2x+6}-dfrac{x}{2x+2}dfrac{3x+2}{left(x+1right)left(x+3right)}
k)d...
Đọc tiếp
4.Giải phương trình
a) \(\dfrac{x+5}{x-5}-\dfrac{x-5}{x+5}=\dfrac{20}{x^2-25}\)
b)\(\dfrac{1}{x-1}+\dfrac{2}{x+1}=\dfrac{x}{x^2-1}\)
c)\(5+\dfrac{76}{x^2-16}=\dfrac{2x-1}{x+4}-\dfrac{3x-1}{4-x}\)
d)\(\dfrac{90}{x}-\dfrac{36}{x-6}=2\)
e)\(\dfrac{1}{x}+\dfrac{1}{x+10}=\dfrac{1}{12}\)
f)\(\dfrac{x+3}{x-3}-\dfrac{1}{x}=\dfrac{3}{x\left(x-3\right)}\)
g)\(\dfrac{3}{x+2}-\dfrac{2}{x-2}+\dfrac{8}{x^2-4}=0\)
h)\(\dfrac{3}{x+2}-\dfrac{2}{x-3}=\dfrac{8}{\left(x-3\right)\left(x+2\right)}\)
i)\(\dfrac{x}{2x+6}-\dfrac{x}{2x+2}=\dfrac{3x+2}{\left(x+1\right)\left(x+3\right)}\)
k)\(\dfrac{x}{x+1}-\dfrac{2x-3}{1-x}=\dfrac{3x^2+5}{x^2-1}\)
l)\(\dfrac{5}{x+7}+\dfrac{8}{2x+14}=\dfrac{3}{2}\)
m)\(\dfrac{x-1}{x}-\dfrac{1}{x+1}=\dfrac{2x-1}{x^2+x}\)
Cần gấp ạ
( \(\dfrac{x+1}{2\left(x-1\right)}+\dfrac{3}{x^2-1}-\dfrac{x+3}{2x+2}\) ). \(\dfrac{4x^2-4}{5}\)
\(\dfrac{x}{x-3}-\dfrac{x^2+3x}{2x+3}.\left(\dfrac{x+3}{x^2-3x}-\dfrac{x}{x^2-9}\right)\)
\(\left(\dfrac{x+1}{x}\right)^2:\left(\dfrac{x^2+3}{x^2}+\dfrac{2}{x+1}.\left(\dfrac{1}{x}+1\right)\right)\)
Giải các phương tình sau:
a) left(12x+7right)^2left(3x+2right)left(2x+1right)3
b)8left(x+dfrac{1}{x}right)^2+4left(x^2+dfrac{1}{x^2}right)^2-4left(x^2+dfrac{1}{x^2}right)left(x+dfrac{1}{x}right)^2left(x+4right)^2
c)2xleft(8x-1right)^2left(4x-1right)0
d)x^2-y^2+2x-4y-100 ( x,y là các số nguyên dương )
Đọc tiếp
Giải các phương tình sau:
a) \(\left(12x+7\right)^2\left(3x+2\right)\left(2x+1\right)=3\)
b)\(8\left(x+\dfrac{1}{x}\right)^2+4\left(x^2+\dfrac{1}{x^2}\right)^2-4\left(x^2+\dfrac{1}{x^2}\right)\left(x+\dfrac{1}{x}\right)^2=\left(x+4\right)^2\)
c)\(2x\left(8x-1\right)^2\left(4x-1\right)=0\)
d)\(x^2-y^2+2x-4y-10=0\) ( x,y là các số nguyên dương )