Åk 6–9

3.3 Algebraic Terms
Earlier you have learned that with addition and subtraction you call those number that you calculate with for terms:

A one variable term always contains these parts:

Sign –
can be positive or negative. You usually do not write the plus sign in the beginning of an expression if the term is positive.

Coefficient – is always a number.  If the number is 1, you usually do not write it out.

Variable – can be one or several letters.

Exponent – is usually a number.  If the number is 1 then you do not write it out.  In advanced mathematics the exponent can even be for example a variable or a fraction.

An algebraic expression consists of one or more terms.

An expression with:
one term is called a monomial, -6x2.
two terms is called a binomial, 3a + b.
three terms is called a trinomial, y2 -2y + 5.

An algebraic expression with three or more terms is usually called a polynomial.

Similar Terms
Two or more terms are similar if they contain the same variable to the same power.

In the expression 3b2 + 2b - b2 are 3b2and b2 similar.

You will learn more about how to calculate with algebraic terms in the next chapter.