\(\left|x-1\right|+\left|1-x\right|=4-x\)
\(\Rightarrow2\left|x-1\right|=4-x\) (1)
+) Nếu x \(\ge\) 1 thì từ (1) suy ra: \(2\left(x-1\right)=4-x\)
\(\Rightarrow2x-2=4-x\)
\(\Rightarrow3x=6\)
\(\Rightarrow x=2\left(t/m\right)\)
+) Nếu x < 1 thì từ (1) suy ra: \(2\left(1-x\right)=4-x\)
\(\Rightarrow2-2x=4-x\)
\(\Rightarrow x=-2\left(t/m\right)\)
Vậy x = \(\pm\) 2
1. Tìm số nguyên x, y biết:
a) \(^{3^{4-x}}=27\)
b) \(^{3^{-1}}.^{4^x}+3.^{4^x}=\dfrac{5}{3}.^{2^7}\)
1. Tìm các số nguyên x,y biết :
a) \(^{3^{4-x}}\)-x = 2
b)3^-1.4^x + 3.4^x = \(\dfrac{5}{3}\).\(^{2^7}\)
tìm x biết
a)3/4+1/4:x=2/5
b)x/-2=-8/x(x khác 0)
c)(x-1)/5=20/x-1
d)(x-3/5)^2=4
Tìm x biết:
a) \(x:\left(-\dfrac{1}{2}\right)^3=-\dfrac{1}{2}\); b) \(\left(\dfrac{3}{4}\right)^5.x=\left(\dfrac{3}{4}\right)^7\)
b2 : tìm x, biết :
a) 1 / (x + 1). (x + 2) + 1 / (x + 2). (x + 3) + 1 / (x + 3). (x + 4) + ... + 1 / (x + 1999). (x + 2000) = 1 / x + 200 = 1/5
( chú ý : / là phần nha )
a ) (-\(\)\(\dfrac{4}{3}\)x + \(\dfrac{1}{2}\))2 = \(\dfrac{1}{4}\)
b) 3 x + 3 x+2= 20
c) ( \(\dfrac{1}{2}\)) x+ (\(\dfrac{1}{2}\))x+2= \(\dfrac{5}{4}\)
Giúp mk với !!! Ngày mai mk làm kiểm tra rồi !!! PLEASE
tìm x: 3^x-1=9^x
tìm x
a, x + 1/2x - 25%x = 10
b, x+x - 1+ x - 2 + x -3 + x - 4 + ... + x-50 = 255
c, 1 + 5 + 9 + 13 + 16 + ... + x =501501
Tìm x biết:
1) \(\dfrac{x+1}{2}+\dfrac{x+1}{3}+\dfrac{x+1}{4}=\dfrac{x+1}{5}+\dfrac{x+1}{6}\)
2) \(\dfrac{x+1}{2009}+\dfrac{x+2}{2008}+\dfrac{x+3}{2007}=\dfrac{x+10}{2000}+\dfrac{x+11}{1999}+\dfrac{x+12}{1998}\)
