Question

Find the sum and product of the roots for each of the following quadratic equations 

(i) x² + 3x – 28 = 0 

(ii) x² + 3x = 0 

(iii) 3 + 1/a = 10/a²

(iv) 3y² – y – 4 = 0

Answer 1

(i) Sum of the roots (α + β) = -3 

Product of the roots (α β) = -28

(ii) Sum of the roots (α + β) = -3 

Product of the roots (α β) = 0

(iii) 3a² + a = 10

3a² + a – 10 = 0 comparing this with x² – (α + β) 

x + αβ = 0

(iv) 3y² – y – 4 = 0