Two questions:
1. What is your goal here? To evaluate the sums?
2. What have you tried so far?
Do you understand what that symbol means? Just replace "i" in "ax(subscript i)+ by(subscrpt i)" by 0, 1, and 2 and add.
Again, replace "j" by 3, 4, and 5 and add.2.
5
∑ (j^3 - 4j^2 - 2j + 3)
j=3
What is j^3- 4j^2- 2j+ 3 when j= 3? That is, what is 3^3- 4(3^2)- 2(3)+ 3? Do the same four j= 4 and 5 and then add those three numbers.