## Precalculus (6th Edition) Blitzer

Need to check the formula. $\sum_{ i=1}^ 2(-1) ^i 2^i=0$ Then, $\sum_{ i=1}^ 2(-1) ^i 2^i=(-1)^1 \cdot 2^1+(-1)^2 \cdot 2^2=2$ But $2 \neq 0$ This implies that $\sum_{ i=1}^ 2(-1) ^i 2^i \neq 0$ Hence, the statement is false.