If A and B are independent events each with positive probability, prove that they cannot be mutually exclusive.

Not to sure about this one but this is what I have:

$\displaystyle \displaystyle P(A\cap B)=P(A)P(B)\Rightarrow P(A|B)=P(A) \ \ \text{and} \ \ P(B|A)=P(B)$

This is all I have.