Page 37 - 新思维数学学生用书9 样章

2 Expressions and formulae

2 1 1 1
i ii iii iv
3y 4 6y 7 2y 2 3y 5

v 5 vi 3 vii 3
4y 2 2y 4 4y 3
a Match each rectangular card with the correct oval card.

b There is one oval card left. Write an expression that simplifies to give the expression on
this card.

In this section, you have used the rules for indices in algebraic
expressions. In Unit 1, you used the rules for indices with numbers.
Do you find it easier to use the rules for indices with expressions or
with numbers, or is there no difference? Why?

Summary checklist

I can use the laws of indices in algebraic expressions.

2.4 Expanding the product of two linear

expressions

In this section you will … Key words

• expand two brackets. brackets

difference of two
When you multiply together two expressions in brackets, you must
squares
multiply each term in the first pair of brackets by each term in the
expand
second pair of brackets.
perfect square

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