Answer
The Sum = -6564
Work Step by Step
Put i = 1 to 7 in 4$(-3)^{i}$.
The Sum = 4$(-3)^{1}$ + 4$(-3)^{2}$ + 4$(-3)^{3}$ + 4$(-3)^{4}$ + 4$(-3)^{5}$ + 4$(-3)^{6}$ + 4$(-3)^{7}$
= (4 $\times$ -3) + (4 $\times$ 9) + (4 $\times$ -27) + (4 $\times$ 81) + (4 $\times$ -243) + (4 $\times$ 729) + (4 $\times$ -2187)
= -12 + 36 - 108 + 324 - 972 + 2916 - 8748 = -6564