An index, power or exponent is a way of shortening expressions such as 4 × 4 × 4 × 4 × 4 to 45.
3p4 is a short way of writing 3 × p × p × p × p.
The 3 is called the coefficient , the p is called the base or variable and the 4 is called theindex, power or exponent.
Indices (plural of index) obey certain rules when they are being multiplied and divided.
Multiplication of terms
When multiplying numbers or variables with indices, add the indices together.
Division of terms
When dividing numbers or variables with indices, subtract the indices.
Raising a term with an index to to another index
If a term with an index is raised to another index then the indices should be multiplied.
There are two rules for "special" indices.