Study the quadratic equation (a−1)x2+2(a+1)x+(a−3)=0, where a is a real parameter and a=1.
a. (i) Obtain an expression for the discriminant in terms of a.
b. (ii) Hence determine the set of values of a for which the roots are
(a) equal and real,
(b) real and distinct,
(c) non-real.
c. (iii) Taking a=2 as a particular case, calculate the roots explicitly and then draw a qualitative sketch of the graph of y=(a−1)x2+2(a+1)x+(a−3) for this value of a, marking intercepts and vertex.