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23 votes
2-7i over -2+5i solve
2-7i/-2+5i

User Nnaelle
by
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1 Answer

19 votes
19 votes

The general rule of division in the complex set is,


(a)/(b)=\frac{a\bar{b}}{b\bar{b}}; a,b\in\mathbb{C}.

If
b=c+di than
\bar{b}=c-di this is called complex conjugate of a complex number.

We have,


a=2-7i


b=-2+5i

The complex conjugate of b is
\bar{b}=-2-5i.

Now perform the algebra,


((2-7i)(-2-5i))/((-2+5i)(-2-5i))=(-4-10i-14i+35i^2)/(4+10i-10i-25i^2)


=(-4-24i-35)/(4+25)=\boxed{(-39-24i)/(29)}

In complex form that is,


-(39)/(29)-(24)/(29)i

Hope this helps :)

User Rwat
by
2.8k points