What is "inverse figures"

Inverse \In*verse"\, a. [L. inversus, p. p. of invertere: cf. F. inverse. See Invert.]

1. Opposite in order, relation, or effect; reversed; inverted; reciprocal; -- opposed to direct.

2. (Bot.) Inverted; having a position or mode of attachment the reverse of that which is usual.

3. (Math.) Opposite in nature and effect; -- said with reference to any two operations, which, when both are performed in succession upon any quantity, reproduce that quantity; as, multiplication is the inverse operation to division. The symbol of an inverse operation is the symbol of the direct operation with -1 as an index. Thus sin-1 x means the arc or angle whose sine is x.

   Inverse figures (Geom.), two figures, such that each point of either figure is inverse to a corresponding point in the order figure.

   Inverse points (Geom.), two points lying on a line drawn from the center of a fixed circle or sphere, and so related that the product of their distances from the center of the circle or sphere is equal to the square of the radius.

   Inverse ratio, or Reciprocal ratio (Math.), the ratio of the reciprocals of two quantities.

   Inverse proportion, or Reciprocal proportion, an equality between a direct ratio and a reciprocal ratio; thus, 4 : 2 : : 1/3 : 1/6, or 4 : 2 : : 3 : 6, inversely.