Question

Va rog ajutatima !! urgent 

Answer 1

i²=-1
(1+i)(3-i)=3+3i-i-i²=3+3i-i+1=4+2i               partea reala =4

(1-i)(4+i)(1+i)=(1-i²)(4+i)=2(4+i)=8+2i          partea reala =8

(2-i)(1-i)(2+i)=(4-i²)(1-i)=5(1-i)=5-5i              partea reala =5