It crops up in Probability Theory, Statistics, Trigonometry, Logarithms , the building of suspension bridges, as well as growth and decay. Along with p , e crops up in many physics formulas . Up to now we have been discussing Real Numbers . There are also Imaginary Numbers . In other words, what number when multiplied by itself gives 4.
Every positive number has two square roots.
Every time you square a number you end up with a positive number. Mathematicians have invented the answer. Without the square root of -1, a lot of mathematics wouldn't make sense. In fact it is no more imaginary than any other number but the name has stuck. So let us have a look at some of the properties of this strange number.