MATHEMATICS · Multi-part · A Level · Mathematics · Algebra and Functions · Algebra and Functions
Problem
Let p(x)=x2−4x+k, where k is a real number.
(a) Calculate the discriminant of p(x) in terms of k.
(b) Find all values of k for which p(x) has exactly two distinct real zeros.
(c) Take k=5. Determine the zeros of p(x) and draw a rough sketch of its graph on the same axes, clearly marking the points where it intersects the x–axis.