To find the value of |2A|, where A is a non-singular (invertible) matrix of order 3 such that A² = 2A, we can use the properties of determinants.
First, let's write down the equation A² = 2A. We can rewrite this equation as:
A² - 2A = 0
Now, factor out A from the left side of the equation:
A(A - 2I) = 0
Where I is the identity matrix of the same order as A.
Since A is non-singular, it means that A - 2I must be the zero matrix, because if A - 2I were invertible, we could multiply both sides of the equation by its inverse to get A = 0, which would contradict the assumption that A is non-singular.
So, we have:
A - 2I = 0
Now, let's solve for A:
A = 2I
Now, we can find |2A|:
|2A| = |2I|
Since the determinant of the identity matrix I of any order is 1, we have:
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To find the value of |2A|, where A is a non-singular (invertible) matrix of order 3 such that A² = 2A, we can use the properties of determinants.
First, let's write down the equation A² = 2A. We can rewrite this equation as:
A² - 2A = 0
Now, factor out A from the left side of the equation:
A(A - 2I) = 0
Where I is the identity matrix of the same order as A.
Since A is non-singular, it means that A - 2I must be the zero matrix, because if A - 2I were invertible, we could multiply both sides of the equation by its inverse to get A = 0, which would contradict the assumption that A is non-singular.
So, we have:
A - 2I = 0
Now, let's solve for A:
A = 2I
Now, we can find |2A|:
|2A| = |2I|
Since the determinant of the identity matrix I of any order is 1, we have:
|2I| = 2³ × |I| = 8 * 1 = 8
So, the value of |2A| is:
b) 8
Given
A²= 2A
Taking Determinant both sides
|A² | = |2A|
|A × A| = |2A|
|A||A| = |2A|
Since order of matrix is 3, using [kA] = k" |A|
|A||A| = 2³|A|
|A||A| = 8|A||
|A||A|8|A|=0
|A| (|A| -8)=0
Thus, |A|0 or |A| = 8
Given that A is a non-singular matrix,
..|A|= 8
Now,
|2A|=2³|A|
= 8×8
= 64
So, the correct answer is (C) = 64