I have M:=√a⋅(b+ic)de and all variables a,b,c,d,e are real. Now I am looking for the real and imaginary part of this, but this square root makes it kind of hard.
Answer
√a(b+ic)de=√ade⋅√b+ic
Let √b+ic=x+iy
⟹b+ic=(x+iy)2=x2−y2+2xyi
Equating the real & the imaginary parts, b=x2−y2,c=2xy
So, b2+c2=(x2−y2)2+(2xy)2=(x2+y2)2⟹x2+y2=√b2+c2
We have x2−y2=b
⟹2x2=√b2+c2+b⟹x2=√b2+c2+b2
⟹x=±√√b2+c2+b√2
and ⟹y2=x2−b=√b2+c2−b2
⟹y=±√√b2+c2−b√2
Now, the sign of y= sign of x⋅ sign of c
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