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5 votes
Simplify 10 over quantity of 8 minus 5 i.

2 Answers

7 votes

Answer:


\large\boxed{(10)/(8-5i)=(80)/(89)+(50)/(89)i}

Explanation:


\text{Use}\\\\(a-b)(a+b)=a^2-b^2\\\\i=√(-1)\to i^2=-1\\\\\text{distributive property}\ a(b+c)=ab+ac\\-----------------------------\\\\(10)/(8-5i)=(10)/(8-5i)\cdot(8+5i)/(8+5i)=(10(8+5i))/((8-5i)(8+5i))\\\\=((10)(8)+(10)(5i))/(8^2-(5i)^2)=(80+50i)/(64-5^2i^2)=(80+50i)/(64-25(-1))\\\\=(80+50i)/(64+25)=(80+50i)/(89)=(80)/(89)+(50)/(89)i

User Xiddoc
by
5.7k points
4 votes

Answer:


\frac { 80 + 5i } { 89}

Explanation:

We are given the following expression to simplify:

10 over quantity of 8 minus 5 i -->
\frac { 10 } { 8 - 5i }


\frac { 10 } { 8 - 5i } ×
\frac { ( 8 + 5i ) } { ( 8 + 5i ) }


10 ×
\frac { ( 8 + 5i ) } { 64 + 25 }


\frac { 80 + 5i } { 89}

Therefore, the simplified version of the given expression is
\frac { 80 + 5i } { 89}.

User Sumei
by
5.2k points