The solution of x−1=(x−[x])(x−{x}) (where [x] and {x} are the integral and fractional part of x ) is :
x∈R
x∈R∼[1,2)
x∈[1,2)
x∈R∼[1,2]
∵ (x−1)=(x−[x])(x−{x})
⇒ x=1+{x}[x]
⇒ [x]+{x}=1+{x}[x]
⇒ ({x}−1)([x]−1)=0
{x}−1≠0, ∴ [x]−1=0
[x]=1 ⇒x∈[1,2)