Question

Find the degree of the polynomial with P(1) = -1 and P(-2) = 3.

• A. -4/3x + 1/3 =0
• B. 4/3x + 1/3 =0
• C. 4/3x - 1/3 =0
• D. -4/3x - 1/3 =0

Answer 1

Answer:

A. -4/3x + 1/3 =0

We have P(x) = ax +b

P(1) = -1

⇒ a + b = -1 .....(1)

P(-2) = 3

⇒ -2a + b = 3 ....(2)

from (1) and (2)

3a = -4

a = $\frac{-4}{3}$

a + b =-1

$\frac{-4}{3}+b=-1$

⇒ b =$-1+\frac{4}{3} = \frac{1}{3}$

So, $P(x) =\frac{-4}{3}x+\frac{1}{3} =0$