| 释义 |
strophoid
 strophoidThe equation for this strophoid isy2 = x2(a + x)/(a - x).stro·phoid S0817700 (strō′foid′)n. The curve traced out by points P and P′ which lie on lines through a fixed point A where the midpoint M of PP′ is on a fixed line and the absolute value │PM│ = the absolute value │P′M│ = the absolute value │MO│, where O is the projection of A onto that fixed line.
[Greek strophos, twisted cord (from strephein, to turn; see streb(h)- in Indo-European roots) + -oid.]strophoid (ˈstrɒfɔɪd) n (Mathematics) a type of curve on a graphstrophoid
strophoid[′strä‚fȯid] (mathematics) A curve derived from a given curve C and two points, called the pole and the fixed point, consisting of the locus of points on a rotating line L passing through the pole whose distance from the intersection of L and C is equal to the distance of this intersection from the fixed point. The special case of the first definition in which C is a straight line and the fixed point lies on C. |