The reciprocal of a number is the number's multiplicative inverse: in other words the number that when you multiply by that number you get 1.
The reciprocal of -2 is `-1/2` since `(-2)(-1/2)=1`
** Note that you do not want to confuse this with a number's opposite, or additive inverse. The additive inverse is a number so that the sum of the numbers is 0. **
Reciprocal of a number is 1/number. It does not affect its sign.
Thus the reciprocal of -2 is `-1/2`