Question

f(x) = -10x³ + 21x² - 5x - 6.
(a) Show that x = 1 is a root of f(x) = -10x³ + 21x² - 5x - 6 (i've already got the answer)
(b) Using the root x = 1, apply polynomial long division to f(x) to calculate the second order polynomial P₂(x) satisfying the relation f(x)=(x 1)P₂(x).
(c) Use the quadratic formula to calculate the roots of P₂(x) and completely factorise the cubic function f. Show all working. Your final answer should clearly show all three linear factors.

Please help me, I'm desperate TT thank you!

Answer 1

answer for the given problem is given