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Calcrivo

Polynomial Expansion

Expand (ax+b)^n using the binomial theorem, showing each term and coefficient.

Inputs

Non-negative integer, max 20

Expanded Form

1x^4 + 8x^3 + 24x^2 + 32x + 16

Number of Terms

5

Step by step

  1. Values used

    a (coefficient of x) = 1; b (constant term) = 2; n (exponent) = 4

  2. Binomial Theorem

    (ax+b)^n = Σ C(n,k) · a^(n-k) · b^k · x^(n-k)

  3. Expanded Form

    = 1x^4 + 8x^3 + 24x^2 + 32x + 16

  4. Number of Terms

    = 5

How it works

The binomial theorem states that (ax+b)^n = Σ C(n,k)·(ax)^(n−k)·b^k for k = 0 to n. Each term's coefficient is a binomial coefficient C(n,k) multiplied by the appropriate powers of a and b.

Formula

Binomial Theorem

(ax+b)^n = Σ C(n,k) · a^(n-k) · b^k · x^(n-k)

n
Exponent
k
Term index
C(n,k)
Binomial coefficient n!/(k!(n-k)!)

Frequently Asked Questions

What is the maximum exponent supported?

The calculator supports exponents from 0 to 20. Beyond that, coefficients become extremely large.

Can I expand (x+1)^5?

Yes — set a=1, b=1, n=5 to get x^5 + 5x^4 + 10x^3 + 10x^2 + 5x + 1.

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