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            Terms of an Algebraic Expressions


            Let us observe an algebraic expressions 2xy + 5. It has two parts,
            i.e., 2xy and 5. Both parts are separated by the operation ‘+’.                 Remember

            These parts are the terms of this algebraic expression 2xy + 5.         Operations multiplication (×)
                                                                                    and division (÷) do not separate
                                                                               2
                                             2
            Let us take another example, a  – 2ab + b , here a , – 2ab, and b       the terms, so 4 × xy  = 4xy  or
                                                                2
                                                       2
                                                                                                         2
                                                                                                                2
            are three terms separated by the operations ‘+’ and ‘–’.                a ÷ b =   a   are considered as a
                                                                                             b
            Thus, the various parts of an algebraic expression which are            single term.
            separated by the arithmetical operations: addition (+) and
            subtraction (–) are called the terms of the algebraic expression.
            Example 11: Write all the terms in the following algebraic expressions:
                                                                            1
                       (a)  2p – 5q + 3          (b)  3xy + 2y – xy    (c)    a – 3ab – b + 1  (d)  4m  – 2lmn
                                                                                                      2

            Solution:                                                       2
                                      Algebraic Expressions                                 Terms
                       (a)    2p – 5q + 3                                  2p, – 5q, and 3

                       (b)   3xy + 2y – xy                                 3xy, 2y, and – xy

                             1                                             1

                       (c)     a – 3ab – b + 1                               a, – 3ab, – b, and 1
                             2                                             2
                                2
                       (d)  4m  –2 lmn                                     4m , –2 lmn
                                                                              2
            Factors of a Term

                                                      3
            Let us take an algebraic expression 2x  – 3xyz.                                Remember
                                                                 3
                                       3
            It consists of two terms 2x  and –3xyz. The term 2x  is a product       When a factor cannot be factorised
            of 2, x, x and x; and –3xyz is the product of –3, x, y and z.           further, it is called an irreducible
                                                                                    factor. E.g., –3,  x,  y and  z are
                                                                         3
            So, we say that 2, x, x, and x are the factors of the term 2x  and      irreducible factors of the term –3xyz.
            –3, x, y, and z are the factors of the term –3xyz.

            Hence, a term is a product of all its factors.
                                                                                                      3
            We can represent the terms and factors of the terms of         Algebraic Expression     2x  – 3xyz
            an algebraic expression conveniently and elegantly by                   Terms      2x 3           –3xyz

            a tree diagram.
                                                                                 Factors   2 x x x         –3 x y z
                                                          3
            The tree diagram for the expression 2x  – 3xyz is as
            shown in the adjacent figure.
            Example 12: Write irreducible factors of each term in the following algebraic expressions.

                 (a)  –ab + 2b – 3a                               (b)  5xy  + 7x y
                                                                               2
                                                                          2
                                                                       4      3
                                                                          2
                       3
                                  2
                 (c)  5x  – 3xy + 2x                              (d)    x −   xy +  5y 2
                                                                       5      4
            Mathematics-7                                      112
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