The sum of zeroes of polynomial 6x2 - 3 - 7x is

Question

Find the sum of zeroes of polynomial 6x² - 3 - 7x is

(a) -7/6

(b) 7/6

(c) 1/2

(d) -1/2

Answer 1

Given,

6x² - 3 - 7x

6x²–7x-3=0

or 6x²–9x+2x-3=0

or 3x(2x-3)+1(2x-3)=0

or (2x-3).(3x+1)=0

or (2x-3)=0, (3x+1)=0

x = 3/2 , -1/3

α=3/2, β= - 1/3 

sum of the zeroes ⇒ α+β =-b/a

                            ⇒ 3/2 - 1/3 = 7/6 = - ( co-efficient of x) / co-efficient of x²

product of the zeroes ⇒αβ = c/a

                                ⇒ -1/3 × 3/2 = -1/2  = constant / co-efficient of x²