The common mistake is to ignore the sign of the base when doing computation involving index.

A simple example illustrates the error that is very common when learning maths.

Example:

Solve 3x

^{2}- 4x + 1 = 0 using the quadratic formula.

Solution:

In solving, we need to extract out the a = 3, b= -4 and c = 1 to fill into the

**quadratic formula**.

However, the quadratic formula requires the utilisation of the b

^{2}- 4ac expression.

Here the mistake is to fill in b

^{2}as -4

^{2}= - 16!

This shouldn't be the case. It should be (-4)

^{2}= 16.

It is a difference of the sign (positive versus negative).

Thus to handle question on indices, you will have to be extra careful on the base and its sign. Make full

**use of parentheses**, if possible, to group and focus the targeted term or number.

*In summary, index or power affects whatever it includes, base and its sign together.*. .

U

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