(x - 2018 ) (x+ 2018 ) = 0
Những câu hỏi liên quan
Tìm giá trị nhỏ nhất
P = 2018/x^2+2x+2017
Q = a^2018+2017/a^2018+2015
A = (x-3y)^2020+(y-2018)^2018
B = (x+y-5)^8+(x-2y)^4+2016
C = \x-2017\+\x-2018\
D = \x-2010\+\x-2011\+\x+2012\
sqrt{x^2+2018}+xsqrt{x^2}x
sqrt{x^2+2018}-x0 sqrt{x^2+2018}-xkhác 0 (left(sqrt{x^2+2018}-xright)left(sqrt{x^2+2018}+xright)left(sqrt{y^2+2018}+yright)2018left(sqrt{x^2+2018}-xright) 2018left(sqrt{y^2+2018}+yright) 2018left(sqrt{x^2+2018}-xright) sqrt{y^2+2018}+ysqrt{x^2+2018}-xChứng minh tương tự sqrt{x^2+2018}+xsqrt{y^2+2018}-yCộng 2 cái vào. Khử được hạng tử. suy ra đc x+y0 rồi tự làm cưng e nhé
Đọc tiếp
\(\sqrt{x^2+2018}+x>\sqrt{x^2}>=x \)
=> \(\sqrt{x^2+2018}-x>0\)
=> \(\sqrt{x^2+2018}-x\)khác 0
=> (\(\left(\sqrt{x^2+2018}-x\right)\left(\sqrt{x^2+2018}+x\right)\left(\sqrt{y^2+2018}+y\right)=2018\left(\sqrt{x^2+2018}-x\right)\)
<=> 2018\(\left(\sqrt{y^2+2018}+y\right)\)= 2018\(\left(\sqrt{x^2+2018}-x\right)\)
<=> \(\sqrt{y^2+2018}+y=\sqrt{x^2+2018}-x\)
Chứng minh tương tự => \(\sqrt{x^2+2018}+x=\sqrt{y^2+2018}-y\)
Cộng 2 cái vào. Khử được hạng tử. suy ra đc x+y=0 rồi tự làm cưng e nhé
tìm x biết (5^2018+5^2018+5^2018+5^2018)+5^2018-5x=0
(5^2018+5^2018+5^2018+5^2018) + 5^2018 -5x=0
5^2018+5^2018+5^2018+5^2018+5^2018-5x =0
5(5^2018)-5x =0
5x =5(5^2018)-0
5x =5(5^2018)
Suy ra x= 5^2018
Vậy: x= 5^2018
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Cho x, y, z >0, x+y+z=2018. C/m biểu thức sau không phụ thuộc vào x:
m = x.\(\sqrt{\frac{\left(y^2+2018\right).\left(z^2+2018\right)}{x^2+2018}}+y.\sqrt{\frac{\left(x^2+2018\right).\left(z^2+2018\right)}{y^2+2018}}+z.\sqrt{\frac{\left(x^2+2018\right).\left(y^2+2018\right)}{z^2+2018}}\)
5x(x-2018)-x+2018=0
x^3-2x=0
Câu a :
\(5x\left(x-2018\right)-x+2018=0\)
\(5x\left(x-2018\right)-x+2018=0\)
\(\Leftrightarrow5x\left(x-2018\right)-\left(x-2018\right)=0\)
\(\Leftrightarrow\left(x-2018\right)\left(5x-1\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x-2018=0\\5x-1=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=2018\\x=\dfrac{1}{5}\end{matrix}\right.\)
Vậy \(x=\dfrac{1}{5}\) hoặc \(x=2018\)
Câu b :
\(x^3-2x=0\)
\(\Leftrightarrow x\left(x^2-2\right)=0\)
\(\Leftrightarrow x\left(x-\sqrt{2}\right)\left(x+\sqrt{2}\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x-\sqrt{2}=0\\x+\sqrt{2}=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\\x=\sqrt{2}\\x=-\sqrt{2}\end{matrix}\right.\)
Vậy \(x=-\sqrt{2}\) ; \(x=0\) hoặc \(x=\sqrt{2}\)
Wish you study well !!
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1: tìm x biết
a, -2018.( x-11)=0\
b, -2018 . (x + 13 ) < 0
c, 2018 (2x - 10 ) >0
d, ( x -3 ) (3x -9 ) = 0
e, ( x-1 0 ( x + 5 ) <0
a, Vì -2018 khác 0
=> x-11=0
=> x=11
b, Vì -2018 < 0
=> x+13 > 0
=> x > -13
c, Vì 2018 > 0 => 2x-10 > 0
=> 2x > 10
=> x > 5
d, => x-3=0 hoặc 3x-9=0
=> x=3
e, Vì x-1 < x+5
=> x-1 < 0 và x+5 > 0
=> x < 1 và x > -5
=> -5 < x < 1
Tk mk nha
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(x+2018)^2020 - (x+2018)^2019 = 0
\(\left(x+2018\right)^{2020}-\left(x+2018\right)^{2019}=0\)
\(\Leftrightarrow\) \(\left(x+2018\right)^{2019}\left(x+2018-1\right)=0\)
\(\Leftrightarrow\) \(\left(x+2018\right)^{2019}\left(x+2017\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}\left(x+2018\right)^{2019}=0\\x+2017=0\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=-2018\\x=-2017\end{matrix}\right.\)
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\(\left(x+2018\right)^{2020}-\left(x+2018\right)^{2019}=0\\ \Leftrightarrow\left(x+2018\right)^{2019}\left[\left(x+2018\right)^2-1\right]=0\\ \Leftrightarrow\left(x+2018\right)^{2019}\left(x+2017\right)\left(x+2019\right)=0\\ \Rightarrow\left[{}\begin{matrix}x+2018=0\\x+2017=0\\x+2019=0\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=-2018\\x=-2017\\x=-2019\end{matrix}\right.\)
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4x(x-2018)-x+2018=0
\(4x\left(x-2018\right)-x+2018=0\)
\(4x\left(x-2018\right)-\left(x-2018\right)=0\)
\(\left(x-2018\right)\left(4x-1\right)=0\)
\(\Rightarrow\orbr{\begin{cases}x-2018=0\\4x-1=0\end{cases}\Rightarrow}\orbr{\begin{cases}x=2018\\x=\frac{1}{4}\end{cases}}\)
xài dấu [ thì nên dùng dấu tương đương nha @greninja
\(4x\left(x-2018\right)-x+2018=0\)
\(\Leftrightarrow4x\left(x-2018\right)-\left(x-2018\right)=0\)
\(\Leftrightarrow\left(4x-1\right)\left(x-2018\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}4x-1=0\\x-2018=0\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=\frac{1}{4}\\x=2018\end{cases}}\)
Vậy x=1/4 hoặc x=2018
Tìm x, y
| x - 2017 | + | y - 2018 | ≤ 0
3| x - y |5 + 10| y + 2/3 |7 ≤ 0
1/2(3/4x - 1/2)2018 + 2017/2018|4/5 y+ 6/25| ≤ 0
2017 |2x - y | 2018 + 2018 | y - 4 |2017 ≤ 0