Iif alpha =3 beta =6 gamma=2 write a cubic polynomial
Answers
Here I am writing alpha as a, beta as b, and gamma as c.
Given f(x) = x^3 - 12x^2 + 44x + c.
Given that a + c = 2b----- (1)
We know that sum of the roots = -b/a
a + b + c = -(-12)/1
= 12 ------ (2)
ab + bc + ca = c/a
= 44/1
= 44 ------------- (3)
abc = -d/a
= -c/1
= -c ------- (4)
From (1) & (4), we get
= > 2b + b = 12.
= > 3b = 12
= > b = 4 ------- (5)
Substitute b = 4 in (1), we get
= > a + c = 2b
= > a + c = 2(4)
= > a + c = 8. ------- (6)
Substitute (5) in (4), we get
= > a(4) * c = -c
= > ac = -c/4 ------- (7)
On solving equation (3), we get
= > ab + bc + ca = 44
= > b(a + c) - c/4 = 44
= > b(8) - c/4 = 44
= > 32 - c/4 = 44
= > -c/4 = 44 - 32
= > -c/4 = 12
= >c = -48.
Therefore the value of c = -48