A Single Term of an Expansion
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State
One term of (a + b)ⁿ can be written without expanding: the term containing bᵏ is C(n, k)·aⁿ⁻ᵏ·bᵏ.
Show
The b³ term of (a + b)⁵ is C(5, 3)·a²·b³ = 10a²b³ — one term fetched alone, with no neighboring terms computed.
Builds on
- Nothing — this is a starting point.
Unlocks
- Nothing yet depends on this.