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Perform the indicated operation and express the result as a simplified complex number. I need help with 35

Perform the indicated operation and express the result as a simplified complex number-example-1
User Chrona
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1 Answer

17 votes
17 votes

Given:-


(3+4i)/(2-i)

To find:-

The simplified form.

At first we take conjucate and multiply below and above.

The conjucate is,


2+i

So now we multiply. we get,


(3+4i)/(2-i)*(2+i)/(2+i)

Now we simplify. so we get,


(3+4i)/(2-i)*(2+i)/(2+i)=(6+3i+8i+4(i)^2)/(2^2-i^2)

We know the value of,


i^2=-1

Substituting the value -1. we get,


\begin{gathered} (6+3i+8i+4(i)^2)/(2^2-i^2)=\frac{6+3i+8i+4(-1)_{}^{}}{2^2-(-1)^{}} \\ \text{ =}(6-4+11i)/(2+1) \\ \text{ =}(2+11i)/(3) \end{gathered}

So now we split the term to bring it into the form a+ib. so we get,


(2+11i)/(3)=(2)/(3)+i(11)/(3)

So the required solution is,


(2)/(3)+i(11)/(3)

User Upinder Kumar
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