Answer
Bit A=0; Bit B=0; Symmetric difference bit=0
Bit A=0; Bit B=1; Symmetric difference bit=1
Bit A=1; Bit B=0; Symmetric difference bit=1
Bit A=1; Bit B=1; Symmetric difference bit=0
Work Step by Step
If the $i$th bit in the string is a 1, then $i$ is in the set.
If the $i$th bit in the string is a 0, then $i$ is not in the set.
If the string A contains a 0 on the $i$th bit and If the string B contains a 0 on the $i$th bit , then the symmetric difference $A \bigoplus B$ contains a 0 on the $i$th bit.
If the string A contains a 0 on the $i$th bit and If the string B contains a 1 on the $i$th bit , then the symmetric difference $A \bigoplus B$ contains a 1 on the $i$th bit.
If the string A contains a 1 on the $i$th bit and If the string B contains a 0 on the $i$th bit , then the symmetric difference $A \bigoplus B$ contains a 1 on the $i$th bit.
If the string A contains a 1 on the $i$th bit and If the string B contains a 1 on the $i$th bit , then the symmetric difference $A \bigoplus B$ contains a 0 on the $i$th bit.
