Polynomials

Exercise 2.2 Part 1

Question 1: Find the value of the polynomial
`5x – 4x^2 + 3` at:

(i) `x = 0`

Answer: Given, `p(x) = 5x – 4x^2 + 3`

Hence, `p(0) = 5 xx 0 – 4 xx 0^2 + 3`

Or, `p(0) = 0 – 0 + 3 = 3`


(ii) `x = - 1`

Answer: Given, `p(x) = 5x – 4x^2 + 3`

Hence, `p(-1) = 5 xx ( - 1) – 4 xx(-1)^2 + 3`

Or, `p(-1) = - 5 – 4 + 3 = - 6`

(iii) `x = 2`

Answer: Given, `p(x) = 5x – 4x^2 + 3`

Hence, `p(2) = 5 x 2 – 4 x 2^2 + 3`

Or, `p(2) = 10 – 8 + 3 = 5`


(iv) `x = 3`

Answer: Given, `p(x) = 5x – 4x^2 + 3`

Hence, `p(3) = 5 xx 3 – 4 xx 3^2 + 3`

Or, `p(3) = 15 – 36 + 3 = - 18`

(v) `x = - 2`

Answer: Given, `p(x) = 5x – 4x^2 + 3`

Hence, `p(-2) = 5 xx (-2) – 4 xx (-2)^2 + 3`

Or, `p(-2) = - 10 – 16 + 3 = - 23`



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