Network & Matrix Computations

David Gleich

Purdue University

Fall 2011

Course number CS 59000-NMC

Tuesdays and Thursday, 10:30am-11:45am

CIVL 2123

In-class quiz 2

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CS 59000-NMC, 30 August 2011
Your name:

Please answer the following questions. You may not use any outside references or technology. Justify and explain all answers. This quiz is for my own evaluation, so that I can provide better instruction in the course.

Question

Consider the vector 1-norm. Show than

$$\normof{\vec{x}}_{\infty} \le \onormof{\vec{x}}{1} \le n \| \vec{x} \|_{\infty}.$$

When is the inequality an equality?