Tìm x, biết:
X : 4 + X x 1,75 = 4040 . Vậy =
Tìm 2 số x,y biết:x-y=125,15 va x/y=2,5/1,75
Tìm x biết:
x(x+5)(x-5)-(x+2)(x^2-2x+4)=42
\(x\left(x+5\right)\left(x-5\right)-\left(x+2\right)\left(x^2-2x+4\right)=42\)
\(\Leftrightarrow x\left(x^2-25\right)-\left(x^3+8\right)=42\)
\(\Leftrightarrow x^3-25x-x^3-8=42\)
\(\Leftrightarrow-25x-8=42\)
\(\Leftrightarrow-25x=42+8\)
\(\Leftrightarrow-25x=50\)
\(\Leftrightarrow x=-\dfrac{50}{25}=-2\)
Tìm x, biết:x*4+x*7+x*9=40300
Ta có : x . 4 + x . 7 + x . 9 = 40300
=> 20 . x = 40300
=> x = 40300 : 20
=> x = 2015
tìm x biết:x/11=x+4/33
Ta có : \(\frac{x}{11}=\frac{x+4}{33}\Rightarrow\frac{3x}{33}=\frac{x+4}{33}\Rightarrow3x=x+4\)
=> 2x = 4
=> x = 2
Tìm x > 0 biết:x(x^3y-x)-x^2(x^2y-2)=4
Tìm x > 0 biết:x(x^3y-x)-x^2(x^2y-2)=4
tìm x biết:x(x^2-25)-(x+2)(x^2-2x+4)=3
Tìm x ϵ Z biết:
x-1/2011 + x-2/2010 - x-3/2009 = x-4/2008
\(\dfrac{x-1}{2011}+\dfrac{x-2}{2010}-\dfrac{x-3}{2009}=\dfrac{x-4}{2008}\)
<=> \(\left(\dfrac{x-1}{2011}-1\right)+\left(\dfrac{x-2}{2010}-1\right)-\left(\dfrac{x-3}{2009}-1\right)=\left(\dfrac{x-4}{2008}-1\right)\)
<=> \(\dfrac{x-2012}{2011}+\dfrac{x-2012}{2010}-\dfrac{x-2012}{2009}-\dfrac{x-2012}{2008}=0\)
<=> \(\left(x-2012\right)\left(\dfrac{1}{2011}+\dfrac{1}{2010}-\dfrac{1}{2009}-\dfrac{1}{2008}\right)=0\)
<=> x - 2012 = 0
<=> x = 2012
Tìm x thuộc Z, Biết:
x+(x+1)+(x+2)+...+(x+2013)=4+1007.2013
Mọi người giúp tui vs
Ta có: \(x+\left(x+1\right)+\left(x+2\right)+...+\left(x+2013\right)=4+1007\cdot2013\)
\(\Leftrightarrow2014x+2027091=2027095\)
\(\Leftrightarrow2014x=4\)
hay \(x=\dfrac{2}{1007}\)