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Concept · Functions & Sequences
Recurrences, summation techniques, and an from Sn
Practice this concept→
A Functions & Sequences set, untimed
Named traps
5 ways this goes wrong.
Each is a named misconception the questions are built to catch. Open one for the move that tempts, and the fix.
- Alternating sign ignoredSums a (-1)n sequence as if all terms were positive, or mispairs terms.→
- Auxiliary sequence not constructedFails to build the transformed/auxiliary sequence needed to solve a recurrence.→
- Mixed-sum parts not separatedFails to split a term into arithmetic and geometric parts before summing.→
- Periodic index reduction errorMisidentifies the period or reduces the index modulo the period incorrectly for a trig-defined sequence.→
- an=Sn-Sn-1 index errorErrs forming an from consecutive partial sums (index or first-term special case).→
Key formulas
No formula sheet is matched to this concept yet. Work it from first principles, and watch the traps.
The full mathematics formula sheet→Shaky underneath?
If the concept underneath still feels loose, patch it here before coming back to CSCA questions.
FoundationsPrecalculus bridgeAlgebra 2 foundations