2 can be written as 2/1 as a rational number, now its reciprocal is 1/2.

Multiplying rational number 2 with it’s reciprocal.

2/1*1/2 = 1,

 
Dividing rational number 2 with it’s reciprocal.
2/1÷1/2 = 2/1*2/1 = 4,
 
Adding rational number 2 with its reciprocal.
2/1+1/2 = (4+1)/2 = 5/2,
 
Subtracting rational number 2 with its reciprocal.
2/1-1/2 = (4-1)/2 = 3/2