Math Problem Statement

simplify using binomial Theorem

Solution

To simplify an expression using the Binomial Theorem, you need to follow the general formula:

(a+b)n=k=0n(nk)ankbk(a + b)^n = \sum_{k=0}^{n} \binom{n}{k} a^{n-k} b^k

Where:

  • (nk)\binom{n}{k} is the binomial coefficient, also called "n choose k," which is calculated as n!k!(nk)!\frac{n!}{k!(n-k)!}.
  • aa and bb are the terms of the binomial.
  • nn is the exponent.
  • kk is the term index, which runs from 0 to nn.

Steps to Simplify:

  1. Identify aa, bb, and nn in your binomial expression (a+b)n(a + b)^n.
  2. Expand the expression using the formula above.
  3. Apply the binomial coefficients (nk)\binom{n}{k} for each term.
  4. Simplify the terms individually.

Example: Simplify (2x+3)3(2x + 3)^3

Using the Binomial Theorem:

(2x+3)3=k=03(3k)(2x)3k(3)k(2x + 3)^3 = \sum_{k=0}^{3} \binom{3}{k} (2x)^{3-k} (3)^k

Expanding this: (2x+3)3=(30)(2x)3(3)0+(31)(2x)2(3)1+(32)(2x)1(3)2+(33)(2x)0(3)3(2x + 3)^3 = \binom{3}{0} (2x)^3 (3)^0 + \binom{3}{1} (2x)^2 (3)^1 + \binom{3}{2} (2x)^1 (3)^2 + \binom{3}{3} (2x)^0 (3)^3

Now calculate the binomial coefficients: (30)=1,(31)=3,(32)=3,(33)=1\binom{3}{0} = 1, \quad \binom{3}{1} = 3, \quad \binom{3}{2} = 3, \quad \binom{3}{3} = 1

Simplifying each term:

  • First term: 1×(2x)3×1=8x31 \times (2x)^3 \times 1 = 8x^3
  • Second term: 3×(2x)2×3=3×4x2×3=36x23 \times (2x)^2 \times 3 = 3 \times 4x^2 \times 3 = 36x^2
  • Third term: 3×(2x)1×9=3×2x×9=54x3 \times (2x)^1 \times 9 = 3 \times 2x \times 9 = 54x
  • Fourth term: 1×1×27=271 \times 1 \times 27 = 27

Thus, the simplified expansion is:

(2x+3)3=8x3+36x2+54x+27(2x + 3)^3 = 8x^3 + 36x^2 + 54x + 27

Would you like more details on this or have any specific binomial expression to simplify?


Here are 5 questions that build on this concept:

  1. How does the binomial coefficient change when the exponent nn increases?
  2. What happens to the expansion when aa or bb is negative in (a+b)n(a + b)^n?
  3. Can the Binomial Theorem be applied to fractional or negative exponents?
  4. What are the practical applications of binomial expansions in calculus or physics?
  5. How does Pascal’s Triangle relate to binomial expansions?

Tip: When simplifying using the Binomial Theorem, always check the powers of aa and bb in each term to avoid errors in the expansion process!

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Algebra
Binomial Expansion
Exponents

Formulas

Binomial Theorem: (a + b)^n = Σ (n choose k) a^(n-k) b^k
Binomial Coefficient: n choose k = n! / (k!(n-k)!)

Theorems

Binomial Theorem

Suitable Grade Level

Grades 9-12