this is my last post ITT
http://en.wikipedia.org/wiki/Order_of_operations
The standard order of operations, or precedence, is expressed in the following chart.
terms inside brackets
exponents
and roots
multiplication
and division
addition and subtraction
A common shorthand is P. E. M. D. A. S. which is an a abbreviation of "Please excuse my dear aunt Sally" or parenthesis, exponent, mutiplication
& division, addition
& subtraction.
This means that if a number or other symbol, or an expression grouped by one or more symbols of grouping, is preceded by one operator and followed by another,
the operator higher on the list should be applied first. The commutative and associative laws of addition and multiplication allow the operators +, −, *, and / to be applied in any order that obeys this rule. The root symbol, √, requires either parentheses around the radicand or a bar (called vinculum) over the radicand. Stacked exponents are applied from the top down.