Algebra: Variables
Sum and product of variables
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The expression #3\times x \times y# is the product of #3#, #x# and #y#. \[3\times x \times y = 3 \cdot x \cdot y\] We can also omit the dot: \[3 \cdot x \cdot y = 3xy\] #3#, #x# and #y# are called the factors of the product. |
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A division of variables can also be seen as a product:
\[\dfrac{x y}{3} = \tfrac{1}{3}xy\]
#\tfrac{1}{3}#, #x# and #y# are the factors of the product.
#\tfrac{1}{3}# is the coefficient of #xy#.
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The expression #x+3y# is the sum of #x# and #3y#. The term #x# can be seen as the product #1\cdot x#. The term #3y# is the product #3\cdot y#. |
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A subtraction of variables can also be seen as a sum:
\[2x-3 y = 2x+-3 y\]
#2x# and #-3 y# are called the terms of the sum.
The term #2x# has coefficient #2# and the term #-3y# has coefficient #-3#.
