x2 + 2ix - 4 = 0 has as its roots

G

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Help me please, I need to know the work for it and an explanation on how I got it, and I'm really confused. :?
 
G'day, Ambeezy.

If we want to solve \(\displaystyle x^2 \, + \, 2ix \, - \, 4 \, = \, 0\) fox x, we can apply the quadratic formula as we would usually.

\(\displaystyle \L x = \frac{-b \, \pm \, \sqrt{b^2 \, - \, 4ac}}{2a}\)

Here: a = 1, b = 2i, c = -4.

Plug them in and remember that \(\displaystyle i^2 = -1\).

See how you go.
 
Hi,

I am trying to practice for a math placement test I have coming up and I came across this problem. I found a post with this problem already but it could only help me so much so far I can get up to:

If we want to solve \(\displaystyle x^2 \, + \, 2ix \, - \, 4 \, = \, 0\) fox x, we can apply the quadratic formula as we would usually.

\(\displaystyle \L x = \frac{-b \, \pm \, \sqrt{b^2 \, - \, 4ac}}{2a}\)

Here: a = 1, b = 2i, c = -4.

Plug them in and remember that \(\displaystyle i^2 = -1\).

Now I understand all of this, but I can't seem to get past:

\(\displaystyle \L x = \frac{-2i \, \pm \, \sqrt{12}}{2}\)

If someone could walk me through the rest of this process, it would be much appreciated.

Thanks,
dkarp520
 
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