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If the sum of square of roots of equatio...

If the sum of square of roots of equation `x^2+(p+iq)x+3i=0` is 8, then find |p|+|q| , where p and q are real.

A

`3`

B

`1`

C

`4`

D

`2`

Text Solution

Verified by Experts

The correct Answer is:
C

Let the roots be `alpha` and `beta`
We have `alpha + beta = -(p + iq),alpha beta = 3i`
Given: `alpha^(2) + beta^(2) = 8`
`or (alpha+beta)^(2) - 2alpha beta = 8`
`or (p + iq)^(2) -6i(2pq-6) = 8`
`or p^(2)-q^(2) + (2pq -6) = 8`
`or p^(2) -q^(2) =8 and pq =3`
`rArr p = 3 and q=1 or p=-3 and q=-1`
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