4 Answers
msp
·2009-05-05 07:56:49
2x-[2x]=x-[x]
x=[x]-[x2]
x=0 for x[0,1/2)
x=-1 for x[1/2,1)
x=1 for x[-1/2,-1)
x=-1 for x(0,-1/2)
Lokesh Verma
·2009-05-06 20:30:49
2x-[2x]=x-[x]
x=[2x]-[x]
so this says that x is an integer because the RHS is an integer
so we have [x]=x and [2x]=2x
hence we have that this is true for only integer values of x :)