**Defined in theory: Physical-quantities****Source code: physical-quantities.lisp****Also defined in:**Scalar-quantities, Unary-scalar-functions

**Documentation:**(RECIP ?x) is the reciprocal element of element ?x with respect

to multiplication operator. For a number x the reciprocal would be 1/x. Not all quantity objects will have a reciprocal element defined. The number 0 for instance will not have a reciprocal. If a parameter x has a reciprocal y, then the product of x and y will be an identity element of some sort such as '1' for numbers, 3*1/3 = 1. The reciprocal of an element is equivalent to exponentiation of the element to the power -1.

(= (Recip ?X) (Expt ?X -1)) (=> (And (Physical-Quantity ?X) (Recip ?X ?Y)) (And (Physical-Quantity ?Y) (= (Quantity.Dimension ?Y) (Expt (Quantity.Dimension ?X) -1))))