They need not be. The four vertices of a quadrilateral are coplanar but NOT collinear. On the other hand, any line (in Eucledian geometry) has an infinite number of points on it - all of which are coplanar.
The fixed points of a function f(x) are the points where f(x)= x.
what is noncollinear because it was a point
3 or more
The shape identified by three noncollinear points.
No. Any two points can be made to form a line.
Any Euclidean plane has infinitely many points.
Since collinear is points that lie on the same line, and you need two points to form a line so those 2 points are collinear. So the opposite of that is noncollinear.