6.4 - 2013 JUNE Q11
11) You are given that f(x) = (2x – 3)(x + 2)(x + 4)
i) Sketch the graph of y = f(x). [3]
ii) State the roots of f(x – 2) = 0. [2]
iii) You are also given that g(x) = f(x) + 15
A) Show that g(x) = 2x3 + 9x2 – 2x – 9. [2]
B) Show that g(1) = 0 and hence factorise g(x) completely. [5]
i) Sketch the graph of y = f(x). [3]
ii) State the roots of f(x – 2) = 0. [2]
iii) You are also given that g(x) = f(x) + 15
A) Show that g(x) = 2x3 + 9x2 – 2x – 9. [2]
B) Show that g(1) = 0 and hence factorise g(x) completely. [5]