Common Mistakes Students Make
Some students often say ‘a minus and a minus is a plus’. This is not correct,
but it is correct to say that ‘a minus times a minus is a plus’. This means when
two negative values are multiplied by each other the result is a positive value.
Some students interpret the information that something was increased by
100% to mean that the new figure is 100 times the old. This is not correct. A
100% increase simply means the old figure was doubled.
Few Things to Remember when you remove a bracket
a
(
)
a
a
(
)
a
(a
)
a
and not
a
Few Things to Remember About Exponents
(
)
(
)
.
1
(
)
( )
( )
Few Things to Remember About Radicals
√
√
√ √
√
√
√
√
√ .√
.
√
Few Things to Remember About Factoring and Special Products
a
ac
a
a(
c)
(a
)(a
)
(a
)
a
a
(a
)
a
a
(a
)
a
a
a
(a
)
a
a
a
2