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Series & Sequences (Foundations)

Core skills for this exam family.

Phase 2 · AP Calculus

Series & Sequences: core idea

Geometric sum S=a1−rS=\frac{a}{1-r} for ∣r∣<1|r|<1.

Example problem: hint and answer

Sum 1+2+3+4+51+2+3+4+5?

Hint: Arithmetic. Answer: 15.

Practice (9 problems — type your answers)

  • 1. Geometric 1+12+14+⋯1+\tfrac12+\tfrac14+\cdots infinite sum?

  • 2. Does ∑1/n2\sum 1/n^2 converge? Type 11 yes, 00 no.

  • 3. Does ∑1/n\sum 1/n converge? Type 11 yes, 00 no.

  • 4. Radius of convergence of ∑xn\sum x^n?

  • 5. Common ratio of 2,6,18,…2,6,18,\ldots?

  • 6. Sum ∑n=032n\sum_{n=0}^{3}2^n?

  • 7. Coefficient of x2x^2 in exe^x Maclaurin?

  • 8. Next term after 1,3,5,71,3,5,7?

  • 9. Sum ∑k=110k\sum_{k=1}^{10}k?

Series & Sequences Practice Problems — Foundations