Matrices & Determinants - 4

DUMB QUESTION

Q1. If co-ordinates (x, y)one rotated by are augleabout the arigin the new coordinetes are represnted by matrix . How ?
Solⁿ :-


Illustration :-
Q1. A = and B 2 show that A B B A .

Solⁿ :- A . B = =

B . A = =

Q 2. Show taht A = is ...of index 3.

Solution :- A² =

A³ = A² - A =

                   =

A³ = 0 i.e. A^k = 0


DETERMINAATS :-

The experssion is colled a determinant.

Calculation of determinants

= a₁ b₂ - a₂ b₁



= a₁ (b₂ c₃ - b₂ b₃) - b₁ (a₂ c₃ - c₂ a₃) + c₁ (a₂ b₃ - b₂ c₃)