If α,β,γ be zeros of polynomial 6x3 + 3x2− 5x + 1, then find the value of α−1+β−1+γ−1.
Answers
We have,
p ( x ) = 6x³ + 3x² - 5x + 1
- a = 6
- b = 3
- c = -5
- d = 1
Therefore, α , β and γ are the zeroes of the polynomial.
★ Sum of zeroes:
α + β + γ = -b/a
⇒ α + β + γ = -3/6
⇒ α + β + γ = -1/2 .....( 1 )
★ Sum of the Product of zeroes :
αβ + βγ + αγ = c/a
⇒ αβ + αγ + βγ = -5/6....( 2 )
★ Product of the zeroes :
αβγ = -d/a
⇒ αβγ = -1/6 .....( 3 )
Now,
α−¹ + β−¹ + γ−¹ [ Given ]
⇒ 1/α + + 1/β + 1/γ
⇒ αβ + αγ + βγ / αβγ
⇒ -5/6 / -1/6 [ 2 & 3 ]
⇒ -5/6 × 6/-1
⇒ -5/-1
⇒ 5
Given:
- We have been given that α, β, γ are the zeros of polynomial 6x³ + 3x² - 5x + 1
To Find:
- We need to find the value of α − 1 + β − 1 + γ − 1.
Solution:
The given polynomial is: 6x³ + 3x² - 5x + 1.
α,β,γ are zeros of this polynomial.
Sum of zeroes: (α + β + γ)
= -b/a
= -3/6
= -1/2
Sum of Product of zeroes (αβ + βγ + γα)
= c/a
= -5/6
Product of zeroes (αβɣ)
= -d/a
= -1/6
Now, we need to find the value of
(α⁻¹ + β⁻¹ + ɣ⁻¹), we have
α⁻¹ + β⁻¹ + ɣ⁻¹
= 1/α + 1/β + 1/ɣ
= (αβ + βɣ + αɣ) / αβɣ
= -5/6 / -1/6
= 5
Hence, the value of α⁻¹ + β⁻¹ + ɣ⁻¹ is 5.