isoperimetricaladj.

1706 Phillips's New World of Words (new ed.) Isoperimeters or Isoperimetrical Figures, such Figures as have equal Perimeters, or Circumferences.

1796 C. Hutton Math. & Philos. Dict. (new ed.) I. 647 M. Cramer too, in the Berlin Memoirs for 1752..proposes to demonstrate..that the circle is the greatest of all isoperimetrical figures, regular or irregular.

1812 D. Cresswell Elem. Treat. Investigation Maxima & Minima i. 49 The greatest of all isoperimetrical polygons, of the same number of sides, is necessarily equilateral.

1828 O. Gregory Hutton's Course Math. (ed. 9) II. 328 Of all isoperimetrical triangles, the one which has the greatest surface is equilateral.

1828 D. Lardner Euclid 72 The area of the square exceeds the area of any other isoperimetrical rectangle by the square of half the difference of the sides of the rectangle.

1743 Philos. Trans. 1742–3 (Royal Soc.) 42 358 Isoperimetrical Problems are resolved..with like Facility by the same Method.

1816 tr. S. F. Lacroix Elem. Treat. Differential & Integral Calculus 463 Such is the simplest case of the Isoperimetrical Problems so called, because at first only curves of the same length were considered.

1821 Blackwood's Edinb. Mag. 10 557 From Cookery up to the Law of Contingent Remainders, Isoperimetrical Problems, or the world-wide difference between Objectivity and Subjectivity.

1865 B. Price Treat. Infinitesimal Calculus (ed. 2) II. xiv. 465 Problems of relative maxima and minima..wherein the variables are not independent of each other, but are connected by some given relation, which may be integral or differential, or in the form of a definite integral..are often called isoperimetrical, because the given condition when interpreted geometrically, is frequently equivalent to the length of the curve being given between certain fixed points or limiting lines.