(5-3i)*2i (5+3i)(2-5i) 4+2i+(-1+6i)(6-i)

Question

(5-3i)*2i
(5+3i)(2-5i)
4+2i+(-1+6i)(6-i)

Answer 1

(5-3i)*2i =10i-6i²=10i+6
(5+3i)(2-5i)=10-25i+6i-15i²=10-19i+15=25-19i
4+2i+(-1+6i)(6-i)=4+2i-6+i+36i-6i²=-2+39i+6=4+39i

Answer 2

1) (5-3i)*2i=10i-6i²=10i+6
2) (5+3i)(2-5i)=10-25i+6i-15i²=-15i²-19i+10
i²=-1 =>-15i²=15
-15i²-19i+10=15-19i+10=25-19i
3) 4+2i+(-1+6i)(6-i)=4+2i-6+i+36i-6i²=-6i²+39i-2
i²=-1 =>-6i²=6
-6i²+39i-2=6+39i-2=4+39i