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| Introduction |
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| Let us consider the marks obtained by four students in Physics, Chemistry and Biology for the first unit test. |
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| We have represented the data in rows and columns. |
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| (i) Rows show the marks obtained by each student. |
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| (ii) The columns show the marks in Physics, Chemistry, Biology obtained by each student. |
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| (iii) The same data can be represented in a rectangular pattern by omitting the headings as given below: |
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| This pattern is generally referred to as 'rectangular array'. It consists of four rows and three columns. It will be seen later on, that this array is called a 4 x 3 (to be read as 4 by 3) matrix. |
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| (iv) The data is put in box brackets to indicate that the whole pattern is to be considered together. |
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| (v) You will notice that the marks obtained by Carl in Chemistry are placed in third row and second column (2 marks). |
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| It is a rectangular array of numbers, arranged in rows and columns. |
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| The number of rows (say m) and the number of columns (say n) determine the order of the matrix. |
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| It is written as m x n (to be read as m by n). |
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| The plural of matrix is matrices. Matrix is usually denoted by capital letters such as A, B, C,… |
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| The above matrix has four rows and three columns. It is called 4 x 3 matrix. |
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| Number of rows x Number of columns indicate the order of a matrix. |
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is a 2 x 2 matrix. It is also called square matrix of order 2. |
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| C = [5 0 3] is a 1 x 3 matrix. It is also called a row matrix. |
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is a 3 x 1 matrix. It is called a column matrix. |
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is not a matrix because column three is incomplete. |
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is a 2 x 3 matrix. It is called a zero matrix or a null matrix. |
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| It is denoted by 02 x 3. |
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