11. Collinear arrays of dipoles are high gain omnidirectional antennas.12. Portable radios usually use collinear arrays of vertical dipoles. 13. In Euclidean geometry, any three non-collinear points determine a plane. 14. Nearly collinear points often lead to numerical instability in computation of the circumcircle. 15. Three non-collinear points in space suffice to determine the orbital plane. 16. Two variables are perfectly collinear if there is an exact linear relationship between them. 17. A complete quadrangle consists of four points, no three of which are collinear . 18. Four distinct points can either be collinear , coplanar or determine the entire space. 19. Then A0, B0, C0 are collinear . 20. Only sound with parallel collinear phase velocity vectors interfere to produce this nonlinear effect.
