sum of the terms of a geometric sequence
- Let (`u_(n)`) be a geometric sequence of common ratio -2, and of first term `u_(0)= 2 `. Let S be the sum of `u_(5)` to `u_(13)`. S=`u_(5)`+`u_(6)`+`u_(7)`+`. . .`+`u_(13)`.
- Calculate `u_(5)`
- Calculate `u_(13)`.
- Deduce S.
Course reminder : Numerical sequences