Question:
Evaluate $i^5+i^{-25}+i^{45}$.

Answer:
We have $i^5 = i^4\cdot i = 1\cdot (i) = i$.  We also have $i^{-25} = 1/i^{25} = 1/(i^{24}\cdot i) = 1/[1\cdot (i)] = 1/i = \frac1{i}\cdot\frac{i}{i} = i/(-1) = -i$ and $i^{45} = (i^{44})\cdot i= 1\cdot i =i$, and . So, adding these three results gives $i^5 + i^{-25} + i^{45} = i+-i+i = \boxed{i}$.