Indices for 3rd Years

Make sure that you understand the work covered in second year. 

Summary for third year.

_

Indices for 2nd Year

Make sure you understand the three rules for indices or powers. The Poweroint and a Summary can be downloaded below. The summary includes reciprocals and scientific notation. For the summer exam you should be able to do these when the base number is represented by a letter.

Be careful with powers of negative numbers. Learn these two examples - this is the way your calculator works.

Orders of Magnitude

There is a famous video which shows very large and very small objects called "Powers of 10", you can see a short version here or the original here.

To find the order of magnitude between two numbers follow these steps

• Both numbers must be written in scientific notation.
• Round off the first part to either 1 or 10, whichever it is closer to.
• Tidy up to just powers of 10.
• Subtract the smaller power from the bigger power - this is your answer (subtract the powers not the numbers).

If there is a very big difference between two numbers then normal rounding off is not very useful. The order of magnitude gives us a rough comparison. For example if the order of magnitude is 2 then one number is about 10² or 100 times bigger than the other. If the order of magnitude is 6 then one number is about 10⁶ or a million times bigger than the other.

Click the link for the PowerPoint used in class, you can view it on-line without any animations or download it to see the animations (it looks better!). Summary for Second Year.

_

Indices and Surds

Indices
The notes below summarise the rules for powers or indices. It is important to know the rules and how to use them. If you understand the rules for multiplication and division then all the other rules follow from this.

Make sure that you know what to do when

• the index is negative
• the index is zero
• the index is a fraction

Notes on Indices The notes open in a new page and if you download them to your computer the maths symbols may be easier to read.

Surds
There are notes below on simple problems with surds and a pencast on some harder examples.

Notes on Surds
 
Angry Surds - this is a great game. You can practice the Pythagorean Theorem, Arithmetic and Surds all at the same time.

This video has lots of examples of working with surds 
(radicals are roots and surds are expressions that have irrational roots)





Pencast on some more complicated examples with surds.

Surds
brought to you by Livescribe


_