Coulomb's formula states that the force of attraction between two electrically charged bodies is k(q1*q2/d^2), where k is 9*10^9 Nm^2/C^2. However, I have a doubt regarding this. We know that like charges repel and unlike charges attract. Let us take the case of like charges first. If both q1 and q2 are like charges, the value of q1*q2 will be positive. As d and k are also positive, the force of attraction will also be positive. However, this means that like charges ATTRACT each other rather than repel. Similarly, if q1 and q2 are unlike charges, then the force of attraction will be negative and this means that unlike charges repel and like charges attract. But this isn't true. So, shouldn't the formula be F= -k(q1*q2/d^2) or |F|=k(|q1*q2|/d^2)?? Please clarify.