Home
Class 12
MATHS
If one root is square of the other root ...

If one root is square of the other root of the equation `x^2+p x+q=0` then the relation between p and q is

A

`p^(3)-q(3p-1)+q^(2)=0`

B

`p^(3)-q(3p+1)+q^(2)=0`

C

`p^(3)+q(3p-1)+q^(2)=0`

D

`p^(3)+q(3p+1)+q^(2)=0`

Text Solution

Verified by Experts

The correct Answer is:
A

Let the roots of `x^(2)+px+q=0` be `alphaand alpha^(2).`
`impliesalpha+alpha^(2)=-pand alpha^(3)=q`
`impliesalpha(alpha+1)=-p`
`impliesalpha^(3){alpha^(3)+1+3alpha(alpha+1)}=-p^(3)["cubing both sides"]`
`impliesq(q+1-3p)=-p^(3)`
`impliesp^(3)-(3p-1)q+q^(2)=0`
Promotional Banner

Similar Questions

Explore conceptually related problems

If p and q are the roots of the equation x^(2)+px+q=0 , then

The roots of the eqaution (q-r)x^(2)+(r-p)x+(p-q)=0 are

If a and beta are the roots of the equation (x^(2)-2x + 3 = 0) from the equation where roots equation is are Q (1)/(alpha)and(1)/(beta)

If one root of the equation 3x^(2)+kx-81=0 is the square of the other then find k.

The equations x^(2) - 4x +a=0 and x^(2) + bx +5=0 have one root in common The other root of these equations are integers in the ratio 3 : 5Find the common root

If the roots of the equation q^2 x^2 + p^2 x + r^2 =0 are the squares of the roots of the equation qx^2 + px + r=0 , then p,q,r are in ………………….. .

If alpha and beta are the roots of the equation (x^(2)-2x + 3 = 0) from the equation where roots equation is are Q (a^(2))/(beta^(2))

If the sum of square of roots of the equation x^2+(p+i q)x+3i=0 is 8, then find the value of pa n dq j ,w h e r epa n dq are real.