∑(x+y)

c. ∑(x+∑(y))
d. ∑x+ ∑y
e. ∑(x)+ ∑(y)*

what do each of these mean?
what's the differences?

3 answers

top line
(1 + 2) + (3 + 4) = 10

= (1+3) + (2 + 4) = 10

associate property of addition d.

as for the rest

c. add y values 2+4 = 6
now 1 + 6 + 3+6 = 16 NO

e. sum of x values + sum of complex conjugates of y values?
Sorry Damon, I am confused can you elaborate?
and use a, b, c, d, e so I know what you are referring to?
This may help as well
X = {2, 2, 9, 5, 6}
Y = {4, 7, 12, 8, 9}