SEQ002 · Sequences & series · Classes 10–12
Sequences and Series
An arithmetic progression adds the same difference each time.
Sequences and Series📐 Formula
aₙ = a + (n − 1)d; Sₙ = n/2 [2a + (n − 1)d]
✏️ Worked example
a = 2, d = 3, n = 5: 2, 5, 8, 11, 14; S₅ = 40.
🌍 Where it is used
Savings plans, seating rows and EMIs.
❓ Quick check
10th term of 3, 7, 11, …: