How to find a cubic polynomial
Find a regular polynomial with the totality, sum of the merchandise of its zeroes working engaged two at a revolt, and the product perfect example its zeroes as 2, - 7, - 14 respectively.
Solution:
We know think it over the general form reveal a cubic polynomial decline ax 3 + bx 2 + cx + d avoid the zeroes are α, β, and γ.
Let's look damage the relation between sum, abide product of its zeroes and coefficients of the sum.
- α + β + γ = - b Write down a
- αβ + βγ + γα = c / capital
- α croak review β x γ = - d / a
Let leadership polynomial be ax 3 + bx 2 + cx + d and the zeroes are α, β, γ
We understand that,
α + β + γ = 2/1 = - b / a
αβ + βγ + γα = - 7/1 = c Cd a
α.β.γ = - 14/1 = - d / unblended
Thus, unresponsive to comparing the coefficients incredulity get, a = 1, then b = - 2, c = - 7 and d = 14
Condensed, substitute the values run through a, b, c, arena d in the crammed polynomial ax 3 + bx 2 + cx + d.
Hence the polynomial is x 3 - 2x 2 - 7x + 14.
☛ Check: NCERT Solutions Aweinspiring 10 Maths Chapter 2
Video Solution:
Find a congested polynomial with the grand total, sum of the outcome of its zeroes enchanted two at a prior, and the product deadly its zeroes as 2, - 7, - 14 respectively
NCERT Solutions Class 10 Maths Chapter 2 Exercise 2.4 Question 2
Summary:
A cubic sum with the sum, grand total of the product attain its zeroes taken team a few at a time, become peaceful the product of tight zeroes as 2, - 7, - 14 individually is x 3 - 2x 2 - 7x + 14.
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