1. The first problem asks to expand the sigma notation $$\sum_{i=1}^5 \frac{2^2}{i}$$ into a series.
2. The formula for sigma notation expansion is to substitute each integer value of $i$ from the lower limit to the upper limit into the expression and sum the results.
3. Here, $2^2 = 4$, so the series is:
$$\frac{4}{1} + \frac{4}{2} + \frac{4}{3} + \frac{4}{4} + \frac{4}{5}$$
4. Evaluating each term:
- $\frac{4}{1} = 4$
- $\frac{4}{2} = 2$
- $\frac{4}{3} \approx 1.333$
- $\frac{4}{4} = 1$
- $\frac{4}{5} = 0.8$
5. Adding these gives the sum:
$$4 + 2 + 1.333 + 1 + 0.8 = 9.133$$
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6. The second problem asks to expand the sigma notation $$\sum_{i=2}^5 (i+4)^2$$ into a series.
7. We substitute $i=2,3,4,5$ into the expression $(i+4)^2$:
- $(2+4)^2 = 6^2 = 36$
- $(3+4)^2 = 7^2 = 49$
- $(4+4)^2 = 8^2 = 64$
- $(5+4)^2 = 9^2 = 81$
8. The series is:
$$36 + 49 + 64 + 81$$
9. Adding these gives the sum:
$$36 + 49 + 64 + 81 = 230$$
Sigma Expansion
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