Question

If p = -2, find the value of:
(i) 4p + 7
(ii) -3p2 + 4p + 7
(iii) -2p3 – 3p2 + 4p + 7

Answer 1

Answer:

(i) 4p + 7

Putting p = -2, we get 4(-2) + 7
= -8 + 7
= -1

(ii) -3p2 + 4p + l
Putting p = -2, we get -3(-2)2 + 4(-2) + 7
= -3 × 4 – 8 + 7 = -12 – 8+ 7
= -13

(iii) -2p3 – 3p2 + 4p + 7
Putting p = -2, we get – 2(-2)3 – 3(-2)2 + 4(-2) + 7
= -2 × (-8) – 3 × 4 – 8 + 7 = 16 – 12 – 8 + 7
= 3