Question

if one zero of cubic polynomial of x3+ax2+bx+c is -1 find other two zero
answer should be b-a+1​

Answer 1

Step-by-step explanation:

Let α,β be the other zeros of the given polynomial x

3

+ax

2

+bx

2

+c

Sum of the zeros =

coefficient of x

3

−coefficient of x

2

⇒−1+α+β=

1

−a

=−a

⇒α+β=−a+1 (i)

Again,

(−1)α+αβ+(−1)β=

coefficient of x

3

−coefficient of x

⇒−α+αβ−β=

1

b

=αβ=b+α+β

α+β=−a+1 , from (i))

=b−a+1