/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Q21E If A and B are invertible matric... [FREE SOLUTION] | 91影视

91影视

If A and B are invertible matrices, then AB must be similar to BA.

Short Answer

Expert verified

The above statement is false.

If A and B are two invertible matrices, then AB may not be similar to BA.

Step by step solution

01

Definition of similar matrix

Let A and B are two square matrices, the matrix A is said to be similar to matrix B if there exists an invertible matrix P such that

B=P-1AP

02

Mentioning concept

Since it is given that matrix A and matrix B are invertible, thenA-1andB-1 exist and are also invertible.

If we multiply the matrix AB by A-1from left and from right, we get the matrix

A-1(AB)A=(A-1A)(BA)A-1(AB)A=BA(A-1A=I)

This shows that matrix BA is similar to matrix AB.

Now, if we multiply the matrix BA by B-1from left and from right, we get the matrix

B-1(BA)B=(B-1B)(AB)B-1(BA)B=AB(B-1B=I)

This shows that matrix AB is similar to matrix BA.

03

Final Answer

If A is an invertible matrix then BA is similar to AB and if B is an invertible matrix then AB is similar to BA.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91影视!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Study anywhere. Anytime. Across all devices.