NIELIT 2017 OCT Scientific Assistant A (IT) - Section B: 7

Question

$M$ is a square matrix of order $’n’$ and its determinant value is $5.$ If all the elements of $M$ are multiplied by $2,$ its determinant value becomes $40.$ The value of $’n’$ is

• A. $2$
• B. $3$
• C. $5$
• D. $4$

Comments

https://gateoverflow.in/336923/Nielit-2017-oct-scientific-assistant-a-cs-section-c-9

Answer 1

let |A|=5  and n*n matrix

after  multiply by each term the determinent become 40 means

2^n*|A|=40

2^n*5=40

2^n=8

2^n=2^3

n=3

|A| IS 3*3 MATRIX