Given the quadratic equation:
x2−3x+r=0
Since α and β are the roots of this equation, by Vieta's formulas, we have:
α+β=3— (1)
αβ=r— (2)
We are also given that 2α and 2β are the roots of the equation:
x2+3x+r=0
Using Vieta's formulas for this equation:
2α+2β=−3⟹α+4β=−6— (3)
(2α)(2β)=αβ=r(which is consistent with (2))
Now, subtract equation (1) from equation (3):
(α+4β)−(α+β)=−6−3
3β=−9⟹β=−3
Substituting β=−3 into equation (1):
α+(−3)=3⟹α=6
Using equation (2), we find r:
r=αβ=6×(−3)=−18
Now, let the roots of the equation x2+6x−m=0 be p and q, where:
p=2α+β+2r
q=α−2β−2r
Substituting the values of α, β, and r:
p=2(6)+(−3)+2(−18)=12−3−36=−27
q=6−2(−3)−2−18=6+6+9=21
For the quadratic equation x2+6x−m=0, the product of the roots is given by −m:
p⋅q=−m
(−27)×21=−m
−567=−m⟹m=567
Thus, the value of m is 567.