f11hw2 - Math 205, Spring 2010 Week 2 (continued): An m n...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Math 205, Spring 2010 Week 2 (continued): An m n matrix A is an array with m horizontal rows; n vertical columns i, j th entry a i,j in the i th row, and j th column. row vector or row n-vector, vectora, is a 1 n matrix, just one row. column vector or column n-vector, vector b, is a n 1 matrix, just one column. 2 Example 1. Give the rows and columns of A = parenleftbigg 2 10 6 5- 1 3 parenrightbigg . What are the entries a 1 , 2 , a 2 , 1 , a 3 , 1 , a 1 , 3 ? The matrix sum, A + B, is defined only when A and B have the same shape; and then the i, j th entry of A + B is a i,j + b i,j , the sum of the i, j th entries of A and B. The scalar multiple of the matrix A by the scalar (number!) c is the matrix with the same shape as A, but with i, j th entry of ca i,j . Matrix multiplication: 1. row n-vector by column m-vector, only when n = m, is the number a 1 b 1 + a 2 b 2 + + a n b n , where the a i are the entries of vectora and the b i are the entries of vector b....
View Full Document

Page1 / 5

f11hw2 - Math 205, Spring 2010 Week 2 (continued): An m n...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online