Question

Write the zeros of the polynomial f(x) = x² – x – 6.

Answer 1

f(x) = x² – x – 6

= x² – 3x + 2x – 6

= x(x – 3) + 2(x – 3)

= (x – 3) (x + 2)

f(x) = 0 ⇒ (x – 3) (x + 2) = 0 

⇒ (x – 3) = 0 or (x + 2) = 0

⇒ x = 3 or x = –2

So, the zeroes of f(x) are 3 and –2.