Question

If f(x) = 2x³ - 13x² + 17x + 12, find 

(i) f(2) 

(ii) f(-3) 

(iii) f(0)

Answer 1

We have, 

f(x) = 2x³ - 13x² + 17x +12 

(i) f(2) = 2 (2)³ – 13 (2)² + 17 (2) + 12 

= (2 x 8) – (13 x 4) + (17 x 2) + 12 

= 16 – 52 + 34 + 12 

= 10

(ii) f (-3) = 2 (-3)³ – 13 (-3)² + 17 (-3) + 12 

= (2 x -27) – (13 x 9) + (17 x -3) + 12 

= -54 – 117 – 51 + 12 

= - 210

(iii) f (0) = 2 (0)³ – 13 (0)² + 17 (0) + 12 

= 0 – 0 + 0 + 12 

= 12