# NCERT Class 12-Mathematics: Exemplar Chapter – 3 Matrices Part 22 (For CBSE, ICSE, IAS, NET, NRA 2022)

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## Fill in the Blanks in Each of the Exercises 68 – 81

Question 68:

________ matrix is both symmetric and skew symmetric matrix.

Null Matrix

Question 69:

Sum of two skew symmetric matrices is always ________ matrix.

Skew symmetric matrix

Question 70:

The negative of a matrix is obtained by multiplying it by ________.

Question 71:

The product of any matrix by the scalar ________ is the null matrix.

Question 72:

A matrix which is not a square matrix is called a ________ matrix.

Rectangular matrix

Question 73:

Matrix multiplication is ________ over addition.

Distributive

Question 74:

If A is a symmetric matrix, then is a ________ matrix.

Symmetrix matrix

Question 75:

If A is a skew symmetric matrix, then is a ________.

Symmetrix matrix

Question 76:

If A and B are square matrices of the same order, then

(i) = ________.

(ii) ________. ( is any scalar)

(iii) = ________.

(i) (ii) (iii)

Question 77:

If A is symmetric, then is a ________. ( is any scalar)

Skew Symmetric matrix

Question 78:

If A and B are symmetric matrices, then

(i) is a ________.

(ii) is a ________.

(i) Skew symmetric matrix

(ii) Neither symmetric nor skew symmetric matrix

Question 79:

If A is symmetric matrix, then is ________.