Question

Tìm x biết :
a) | 2x - 1 | = 4
b) -3 | 2x | + | 5 - x | = 1
c) 2^x + 3 = 2^x - 1 = 15/64
d) | -3 + 5 | = x
e) ( x - 1 )^100 + ( x - y )^98 = 0
f) ( x - 7 )^x + 1 - ( x - 7 )^x + 5 = 0

Answer 1

a: =>2x-1=4 hoặc 2x-1=-4

=>2x=5 hoặc 2x=-3

=>x=5/2 hoặc x=-3/2

d: =>x=|2|=2

e: \(\Leftrightarrow\left\{{}\begin{matrix}x-1=0\\x-y=0\end{matrix}\right.\Rightarrow x=y=1\)