I am supposed to identify the imaginary part (marked in bold) of each expression, just wanted to see if I got them correct:(adsbygoogle = window.adsbygoogle || []).push({});

1. (1+i)+(1-i) ..........................0

2. (5+i)+(1+5i) ..........................6

3. (5+i)-(1-5i) ..........................6

4. 1+2i+3+4i+5 ..........................6

5. [tex]S=1+\frac{1}{2i}+\frac{1}{4}+\frac{1}{8i}+\frac{1}{16}+\frac{1}{32i}+\frac{1}{64}+...[/tex]

using the geometric series: (.5)/(1-.25)=2/3=1/1.5i

does this mean the imaginary part is 1.5 since theis in the denominator? or is it 1.5?i

6. a and b are constants

a+bi ..........................b

7. (a+ib)^2 ..........................2ab

8. (a+bi)(b+ia) ..........................a^2+b^2

9. (ia)^3 ..........................-a^3

10. a(a+i)(a+2i) ..........................3a^2

are these correct?

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# Identify the imaginary part

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