A quadratic polynomial whose zeroes are 5 and -3, is (a) x2 + 2x - 15

1.	A quadratic polynomial whose zeroes are 5 and -3, is (a) x2 + 2x - 15 (b) x2 - 2x + 15 (c) x2 – 2x – 15 (d) none of these
Answer» (c) x² – 2x – 15 Here, the zeroes are 5 and –3. Let α = 5 and β = –3 So, sum of the zeroes, α + β = 5 + (–3) = 2 Also, product of the zeroes, αβ = 5 × (–3) = –15 The polynomial will be x² – (α + β) x + αβ ∴ The required polynomial is x² – 2x – 15.

A quadratic polynomial whose zeroes are 5 and -3, is (a) x2 + 2x - 15 (b) x2 - 2x + 15 (c) x2 – 2x – 15 (d) none of these

Answer»

(c) x² – 2x – 15

Here,

the zeroes are 5 and –3.

Let α = 5 and β = –3

So,

sum of the zeroes, α + β = 5 + (–3) = 2

Also, product of the zeroes, αβ = 5 × (–3) = –15

The polynomial will be x² – (α + β) x + αβ

∴ The required polynomial is x² – 2x – 15.