(a) Prove that () = 1, (n) = 1, and (^)= (₁ = ¹) + n if 1≤k ≤n-1. (b) Use part (a) and induction to prove that (2) is a positive integer for all n, k = Z such that 0≤ k ≤n. (c) Let x, y E R. Prove that for every integer n ≥ 0, n (x + y)² = Σ (1) xn-kyk, k=0

Advanced Engineering Mathematics
10th Edition
ISBN:9780470458365
Author:Erwin Kreyszig
Publisher:Erwin Kreyszig
Chapter2: Second-order Linear Odes
Section: Chapter Questions
Problem 1RQ
icon
Related questions
Question
**Problem 5:**

For \( n, k \in \mathbb{Z} \) such that \( 0 \leq k \leq n \), define

\[
\binom{n}{k} = \frac{n!}{k!(n-k)!}.
\]

Note that, by convention, \( 0! = 1 \).

**(a)** Prove that \( \binom{n}{0} = 1 \), \( \binom{n}{n} = 1 \), and 

\[
\binom{n}{k} = \binom{n-1}{k} + \binom{n-1}{k-1}
\]

if \( 1 \leq k \leq n-1 \).

**(b)** Use part (a) and induction to prove that \( \binom{n}{k} \) is a positive integer for all \( n, k \in \mathbb{Z} \) such that \( 0 \leq k \leq n \).

**(c)** Let \( x, y \in \mathbb{R} \). Prove that for every integer \( n \geq 0 \),

\[
(x + y)^n = \sum_{k=0}^{n} \binom{n}{k} x^{n-k}y^k.
\]
Transcribed Image Text:**Problem 5:** For \( n, k \in \mathbb{Z} \) such that \( 0 \leq k \leq n \), define \[ \binom{n}{k} = \frac{n!}{k!(n-k)!}. \] Note that, by convention, \( 0! = 1 \). **(a)** Prove that \( \binom{n}{0} = 1 \), \( \binom{n}{n} = 1 \), and \[ \binom{n}{k} = \binom{n-1}{k} + \binom{n-1}{k-1} \] if \( 1 \leq k \leq n-1 \). **(b)** Use part (a) and induction to prove that \( \binom{n}{k} \) is a positive integer for all \( n, k \in \mathbb{Z} \) such that \( 0 \leq k \leq n \). **(c)** Let \( x, y \in \mathbb{R} \). Prove that for every integer \( n \geq 0 \), \[ (x + y)^n = \sum_{k=0}^{n} \binom{n}{k} x^{n-k}y^k. \]
Expert Solution
steps

Step by step

Solved in 2 steps with 2 images

Blurred answer
Recommended textbooks for you
Advanced Engineering Mathematics
Advanced Engineering Mathematics
Advanced Math
ISBN:
9780470458365
Author:
Erwin Kreyszig
Publisher:
Wiley, John & Sons, Incorporated
Numerical Methods for Engineers
Numerical Methods for Engineers
Advanced Math
ISBN:
9780073397924
Author:
Steven C. Chapra Dr., Raymond P. Canale
Publisher:
McGraw-Hill Education
Introductory Mathematics for Engineering Applicat…
Introductory Mathematics for Engineering Applicat…
Advanced Math
ISBN:
9781118141809
Author:
Nathan Klingbeil
Publisher:
WILEY
Mathematics For Machine Technology
Mathematics For Machine Technology
Advanced Math
ISBN:
9781337798310
Author:
Peterson, John.
Publisher:
Cengage Learning,
Basic Technical Mathematics
Basic Technical Mathematics
Advanced Math
ISBN:
9780134437705
Author:
Washington
Publisher:
PEARSON
Topology
Topology
Advanced Math
ISBN:
9780134689517
Author:
Munkres, James R.
Publisher:
Pearson,