Tìm x, biết: sorry vì hỏi tiếp
x2 - 2015x + 2014=0
Tìm x biết \(|2015x-2014|\)=\(|2015x+2014|\)
\(|2015x-2014|=|2015x+2014|\)
\(\Leftrightarrow\orbr{\begin{cases}-2015x+2014=|2015x+2014|\left(l\right)\\2015x-2014=|2015x+2014|\left(n\right)\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}2015x+2014=-2015x+2014\\2015x+2014=2015x-2014\end{cases}\Leftrightarrow\orbr{\begin{cases}4030x=0\\0x=-4028\left(l\right)\end{cases}\Leftrightarrow}4030x=0\Leftrightarrow x=0}\)
x^2-2015x+2014=0 hãy tìm x
<=>(x2-x)-(2015x-2014)=0
<=>x(x-1)-2014(x-1)=0
<=>(x-2014)(x-1)
<=>x-2014=0
hoặc x-1=0
<=>x=2014
hoặc x=1
h
\(x^2-2015x+2014=0\)
\(\Leftrightarrow x^2-2014x-x+2014=0\)
\(\Leftrightarrow x\left(x-2014\right)-\left(x-2014\right)=0\)
\(\Leftrightarrow\left(x-1\right)\left(x-2014\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}x-1=0\\x-2014=0\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=1\\x=2014\end{cases}}\)
Tìm x biết
a, X2-2015x+2014=0
b, x3 -4x =0
Đung mk tick
\(x^2-2015x+2014=0\)
\(x^2-x-2014x+2014=0\)
\(x\left(x-1\right)-2014\left(x-1\right)=0\)
\(\left(x-1\right)\left(x-2014\right)=0\)
TH1:x -1 = 0
=>x=1
TH2 : x-2014=0
=> x=2014
\(x^3-4x=0\)
\(x\left(x^2-4\right)=0\)
\(x\left(x-4\right)\left(x+4\right)=0\)
TH1: x=0
TH2:x-4=0
=> x= 4
TH3: x+4=0
=> x=(-4)
Hok tốt
tìm x,y,z t/m:
a, x^4-2014x^2+2015x-2014=0
b, 9x^2+y^2+2z^2-18x+4z-6y+20=0
c, x^4+2016x^2+2015x+2016=0
a) Tìm nghiệm của đa thức : P(x) = x^2016 - x^2014
b) Cho đa thức Q(x) = -x^2016 + 2015x -1 có nghiệm là âm không ? Vì sao?
a) \(P\left(x\right)=0\Rightarrow x^{2016}-x^{2014}=0\Rightarrow x^{2014}\left(x^2-1\right)=0\)
TH1: \(x^{2014}=0\Rightarrow x=0\)
TH2: \(x^2-1=0\Rightarrow x=\pm1\)
Vậy \(P\left(x\right)\) có nghiệm là \(x=0,x=1,x=-1\)
b) Xét \(x< 0\)
Ta có: \(x^{2016}>0\Rightarrow-x^{2016}< 0\); \(2015x< 0\)
\(\Rightarrow Q\left(x\right)=-x^{2016}+2015x-1< 0\)
Vậy \(Q\left(x\right)\) không có nghiệm âm
a, Đặt \(P\left(x\right)=x^{2016}-x^{2014}=0\Leftrightarrow x^{2014}\left(x^2-1\right)=0\Leftrightarrow x=0;x=-1;x=1\)
tìm x, biết :
|x+1| + |x+2| + |x+3| +...+ |x+2014| = 2015x
=> x là số nguyên dượng
=> x+1+x+2+x+3+x+4+...+x+2014=|x+1|+|x+2|+|x+3|+|x+4|+...+|x+2014|=2015
=> 2014x + (1+2+3+4+...+2014)=2015x
=> 1+2+3+4+...+2014=x
tìm x thỏa mãn x4-2014x2+2015x-2014=0
x^4-2014x^2+2015x-2014=0
<=>x4+x-2014x2+2014x-2014=0
<=>x.(x3+1)-2014.(x2-x+1)=0
<=>x.(x+1)(x2-x+1)-2014.(x2-x+1)=0
<=>(x2+x+1)[x.(x+1)-2014]=0
<=>x.(x+1)-2014=0 (vì x2+x+1 >0)
giải tiếp sao số xấu thế
tìm x biết:
|x+1|+|x+2|+|x+3|+|x+4|+....+|x+2014| = 2015x
tìm x biết: |x+1|+|x+2|+|x+3|+..........+|x+2014|=2015x
|x+1| + |x+2| + |x+3| + .......... + |x+2014| = 2015x
Ta có :
|x+1| \(\ge\)0
|x+2| \(\ge\)0
|x+3| \(\ge\)0
..........
|x+2014| \(\ge\)0
=> |x+1| + |x+2| + |x+3| +..........+ |x+2014| \(\ge\)0
=> 2015x \(\ge\)0
Mà 2015 \(\ge\)0
=> x \(\ge\)0
=> |x+1| + |x+2| + |x+3| +..........+ |x+2014|
= x + 1 + x + 2 + x + 3 +.................... + x + 2014 = 2015x
=> 2014x + (1 + 2 + 3 +............ + 2014) = 2015x
=> 1 + 2 + 3 + 4 + ........................ + 2014 = x
=> x = 2029105