Answer:
18i, -7-i, -6+18i
Step-by-step explanation:
1. √-324
first take out the negative as √-1=i
√-324= i√324
324 =2*162
324=2*2*81
324=2*2*9*9
i√324=i√2*2*9*9= i* 2*9= 18i
3.
-4+7i-3-8i combine like terms
-4-3 -8i+7i = -7-i
5.
(1+5i)(4-2i) distribute
1*4 -1*2i +5i*4 -5i*(-2i) multiply
4 -2i +20i +10i² but i²= -1 so
4 -2i +20i -10 combine like terms
-6 +18i
