Question

Evaluate the summation of 3 times negative 2 to the n minus 1 power, from n equals 1 to 5..

−93
−33
33
93

Answer 1

For n = [1,2,3,4,5]  you can evaluate the series as follows:

$3( -2)^{1-1} +3( -2)^{2-1} +3( -2)^{3-1} +3( -2)^{4-1}+3( -2)^{5-1}$
= 3 + (-6) + (12) + (-24) + (48)
= 63 - 30
= 33

Answer 2

he is correct, the answer is 33