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juantheron
Jul9-11, 01:19 PM
Given that the equation z^2+(p+iq)z+r+is=0, where p,q,r,s are real and non-zero root then
which one is right
1. pqr=r^2+p^2s
2. prs=q^2+r^2p
3. qrs=p^2+s^2q
4. pqs=s^2+q^2r
1. The problem statement, all variables and given/known data
2. Relevant equations
3. The attempt at a solution
What have you tried?
Where are you stuck?
To start, let z = x + y i , where x & y are real.
I assume i 2 = -1
juantheron
Jul10-11, 03:58 AM
put z=x+iy(x+iy)^2+(p+iq)(x+iy)+r+is=0 x^2-y^2+2ixy+px-qy+i(qx+py)+r+is=0\left(x^2-y^2+px-qy+r\right)+i\left(qx+py+2xy+s\right)=0+i.0\left(x ^2-y^2+px-qy+r\right)=0\left(qx+py+2xy+s\right) = 0
Now I am struck here.
Given that the equation z^2+(p+iq)z+r+is=0, where p,q,r,s are real and non-zero root then
which one is right
...
Sorry for my lame suggestion !
Use the quadratic formula to solve for z, then the part of the instructions which seem to be missing some words; in bold below.
... p,q,r,s are real and non-zero root ...
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