Give an example of an irrational number and how you mat use it or come across in the real world.
An irrational number is any real number which can not be expressed in the form of p/q , where p and q are integers.The irrational are many and uncountable.
Some examples: e, pi and sqrt19.
We know e = Lt (1+1/x)^x as n--> infinity. The value of e is like 2.71828...
We know pi = Length of circumference of a circle/length of diameter of that circle. the value of pi is like 3.14159...
Square root 19. The value we know is between 4 and 5.
The knowledge of pi is essential in geometry. It is used to know the length of circumference given the radius or diameter.
Rather than use , the invention of irrational number has contributed to the completeness of the idea of numbers. It gave a sense of enlightement that between any two distinct perfect square roots , there are still more square roots which need not be in p/q form alone.