The parametric vector form of a B-spline curve was defined in the Practice Problems as
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a. Show that for 0 ≤ t ≤ 1, x(t) is in the convex hull of the control points.
b. Suppose that a B-spline curve x (t) is translated to x (t) + b (as in Exercise 1). Show that this new curve is again a B-spline.