GAMSAT doesn’t have a mathssection. Nevertheless, you can’t deny the fact that numerical abilities are quite critical to crack the exam. Four out of five GAMSAT takers don’t make it to med-school. One of the reasons of failure is poor mathematical aptitude. It’s no mystery that section 3 carries the maximum weightage among all the 3 GAMSAT sections and many of the science questions need a considerable amount of calculations. Calculators aren’t allowed in GAMSAT and you don’t have to be a number-crunching machine to solve the numerical questions. Many of the questions will ask for an approximate answer. To estimate the approximate answers you need to have the basic mathematical concepts in your fingertips. Logarithm is one such topic, which you should be very clear upon to solve GAMSAT questions.

**What is logarithm**

John Napier of Merchiston, a Scottish mathematician, physicist and astronomer, invented logarithm in early 17^{th} century. When any number *a* is raised to the power of number *b*, i.e., the multiplication of *b* factors, each of which is equal to *a*, the result is called the exponentiation. Symbolically,

**a ^{b} = c**, where

**a**is the base,

**b**is the index or exponent and the product

**c**is the exponentiation, sometimes called the power.

Logarithm is the inverse function of exponentiation. By definition, the logarithmic value of number **b** to the base **a** is the number or index by which the base **a** must be raised to get **b**.

Symbolically,

If **a ^{b} = c, **then

**log**

_{a}c=bThe idea becomes clear if you look at the following equation:

Like any other pair of a function and its inverse, the logarithmic and exponential functions are also inverse functions of each other. This means that both the graphs are symmetrical to each other about the line *y = x*

In the next article, we’ll deal with the practical application of logarithms in GAMSAT.