f(x) is a discontinous function only at x=0 such that ( f(x) )2=1 for all values of x ε R , then the numbers of such functions is :
A. 3
B. 2
C. 6
D. 4
Actually i am getting it as 4 but the answer given is 6 .... now is the answer wrong or am i not getting the other two such functions !!
the functions that i could make out are :
1. for all x ε R - , f(x) = -1 ; for x=0 ,f(x)=-1 and for all x ε R+ ,f(x)=1
2. for all x ε R- ,f(x)=-1 ; for x=0 ,f(x)=1 and for all x ε R+ ,f(x) =1
3. for all x ε R-, f(x) =1 ; for x=0 , f(x) =1 and for all x ε R+,f(x)= -1
4. for all x ε R- ,f(x)= 1 ; for x=0 , f(x)=-1 and for all x ε R+ , f(x) = -1 please help