Add some maths' functions

[Owais28]

List of some important functions

• Absolute number
• Aliquot Sum of a number
• Area of various shapes
• Arithmetic-Geometric Mean
• Armstrong number
• Average Mean
• Average Median
• Binary to Decimal conversion
• Binary Exponentiation Iterative
• Decimal to Binary conversion
• Binomial Coefficient
• Bisection Method
• Function to check Co-prime
• Decimal Expansion
• Decimal Isolation
• Degree to Radian Conversion
• Euler Method
• Eulers Totient
• Factorial
• Factors
• Fibonacci
• Find HCM
• Find LCM
• Finding a minimum in a array of numbers
• Function to check a number is Divisible by another number or not
• Function to check a number is Even
• Function to check a number is Odd
• Function to check a number is Pronic
• Function to check a number is Square free
• Juggler Sequence
• Leap year
• Matrix Multiplication
• Number of digits in a number
• Pascal Triangle
• Perfect Cube
• Perfect Square
• Perfect Numbers
• Prime check
• Radian to Degree Conversion
• Finding Square root
• Sum of Digits of a given number

[Rajat379]

Raised a PR to check perfect square - #37

[skyfrk]

I implemented Factorial in #38

[skyfrk]

I implemented Sum of Digits of a given number in #39

[skyfrk]

I implemented IsLeapYear (gregorian calendar) in #40

[appgurueu]

I implemented IsLeapYear (gregorian calendar) in #40

Just link #40 to #10 then (as you did), no need to add a redundant comment (and trigger a redundant notification here).