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
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 )
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) \(\dfrac{x+1}{2009}+\dfrac{x+2}{2008}+\dfrac{x+3}{2007}=\dfrac{x+10}{2000}+\dfrac{x+11}{1999}+\dfrac{x+12}{1998}\)
Tìm x : (x-1)^x+2 =(x-1)^x+6
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
(x- 3) ^ x - (x -3) ^ x+2
(x-1,2)^2=4
(x+1)^3=-125
(x+1,5)^8+(2,7-y)^10=0
3^-1.4^x+ 3.$^x+5/3. 27
9^-x. 27^x= 243
tìm x, biết:
a) (2x-4)x+1=(2x-4)x+5
b) (x-3)x+4=(x-3)x+7
Tìm x, biết:\(\frac{x+2}{2019}+\frac{x+3}{2018}+\frac{x+4}{2017}+\frac{x+5}{2008}+\frac{x+2076}{11}=0\)