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3-4i/2+iCan you help me to solve this problem please

User Lytesha
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1 Answer

5 votes

To solve this problem, we multiply and divide the given expression by 2-i:


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

Recall that:


(a+ib)(a-ib)=a^2+b^2.

Therefore:


(3-4i)/(2+i)((2-i)/(2-i))=((3-4i)(2-i))/(2^2+1^2)=((3-4i)(2-i))/(5).

Finally, multiplying the factors in the numerator, we get:


(6-3i-8i-4)/(5).

Finally, simplifying the above result, we get:


(2-11i)/(5)=(2)/(5)-(11)/(5)i.

Answer:


\begin{equation*} (2)/(5)-(11)/(5)i. \end{equation*}

User Or Neeman
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