To find a quadratic equation whose roots are βα and αβ, we first determine the sum and the product of these roots.
Let the roots be r1=βα and r2=αβ.
The sum of the roots is:
S=r1+r2=βα+αβ=αβα2+β2
The product of the roots is:
P=r1⋅r2=βα⋅αβ=1
We are given:
α+β=−p
α3+β3=q
Using the algebraic identity for the sum of cubes:
α3+β3=(α+β)3−3αβ(α+β)
Substitute the given values into the identity:
q=(−p)3−3αβ(−p)
q=−p3+3pαβ
Since p=0, we can solve for the product αβ:
3pαβ=p3+q⟹αβ=3pp3+q
Next, we express α2+β2 in terms of p and q:
α2+β2=(α+β)2−2αβ
α2+β2=(−p)2−2(3pp3+q)=p2−3p2(p3+q)
α2+β2=3p3p3−2p3−2q=3pp3−2q
Now, substitute α2+β2 and αβ into the expression for S:
S=αβα2+β2=3pp3+q3pp3−2q=p3+qp3−2q
The quadratic equation with roots r1 and r2 is given by:
x2−Sx+P=0
x2−(p3+qp3−2q)x+1=0
Since p3=−q, we can multiply the entire equation by (p3+q):
(p3+q)x2−(p3−2q)x+(p3+q)=0
Therefore, the correct option is B.