Find:

Question

Re[1/(2+j)]
Im[2+j/(3+4j)]

Answer 1

Rationalize the denominator by multiplying top and bottom by 2-j
1/(2+j)
=(2-j)/((2+j)(2-j))
=(2-j)/(4-j²)
=(2-j)/5
=(2/5)-(j/5)
Can you take it from here?
The next one is similar.

Answer 2

Yes, thank you. I was doing it that way, but didn't know if I was correct.

Answer 3

Good, keep up the good work!