2. Find a cubic polynomial with the sum, sum of the product of its zeroes
taken two at a time, and the product of its zeroes are 3, 0,- 4, respectively.
Answers
Answer :
x³ + 3x² + 4
Step-by-step explanation :
Given,
sum of the zeroes = 3
sum of the product of its zeroes taken two at a time = 0
the product of its zeroes = - 4
The cubic polynomial will be in the form of :
⇒ x³ - (sum of zeroes)x² + (sum of the product of its zeroes taken two at a time)x - (product of zeroes)
⇒ x³ - 3x² + (0)x - (-4)
⇒ x³ - 3x² + 0 + 4
⇒ x³ - 3x² + 4
Generally,
A cubic polynomial say, f(x) is of the form ax3 + bx2 + cx + d.
And, can be shown w.r.t its relationship between roots as.
⇒ f(x) = k [x3 – (sum of roots)x2 + (sum of products of roots taken two at a time)x – (product of roots)]
Where, k is any non-zero real number.
Here,
f(x) = k [x3 – (3)x2 + (-1)x – (-3)]
∴ f(x) = k [x3 – 3x2- x + 3)]
where, k is any non-zero real number.