CBSE · Class 6-12

Class 11 · Mathematics (041)

Unit 7 · Class 11Mathematics (041)

Algebra

Binomial Theorem

$(a + b)^n$ expansion for positive integer $n$ using binomial coefficients.

Formative-only for boards

General and middle terms in binomial expansion

Learn these concepts — they won't appear in the CBSE 2026-27 board paper.

Lessons

3 concepts

1
Binomial Expansion
$(a + b)^n = \sum_{k=0}^{n} {}^nC_k\, a^{n-k} b^k$ .
2
General Term
$T_{r+1} = {}^nC_r\, a^{n-r} b^r$ . Read off any term without full expansion.
3
Pascal's Triangle
Rows give binomial coefficients. Symmetry: ${}^nC_r = {}^nC_{n-r}$ .

Skills to practise

Skill · medium

Binomial Theorem — Practice (coming soon)

Practice bank for this unit is in progress. You can still read the lessons above.