Definition of Additive Inverse The additive inverse of a number is another number you add to a number to create the sum of zero. In other words, additive inverse of x is another number, for examle y, as long as the sum of x + y equals zero. The additive inverse of x is equal

## Circle: Definition, Parts, Area, Perimeter, Examples

Circle is one of familiar shape in daily life. It was studied since long time ago. There are many things that is circle such as clock,  wheel, gear, ring, coins, etc.. Definition of Circle Circle is two-dimensional shape. It is set of points that has same distane from the center in a plane. In another words, there are

## Composite Number

Composite number is a whole number that can be made by multiplying other whole numbers. Example: 10 can be made by 5 × 2 so is a composite number. Not Composite number 5 = 1 × 5, Is not composite number because 1 × 5 isn’t using other whole numbers 7 = 2 × 3.5, Is

## Equivalent Fractions

Equivalent Fractions have the same value, even though they may look different. These fractions are really the same: Why are they the same? Because when you multiply or divide both the top and bottom by the same number, the fraction keeps it’s value. The rule to remember is: “Change the bottom using multiply or divide,

## Invers of Matrix: Gauss Jordan & Minor-Cofactor Methods, Examples

Invers of a matrix relate with identity of a matrix. It is symbolized by “X-1” where “X” is a matrix X. if there is matrix A, then the invers is A-1. The result of multiplication between matrix A and A-1 is identity matrix “I”. In mathematics symbol, it is written as A.A-1 = I or A-1.A =

## Homogeneous Differential Equations

A Differential Equation is an equation with a function and one or more of its derivatives: Example: an equation with the function y and its derivative Homogeneous Differential Equations A first order Differential Equation is Homogeneous when it can be in this form: We can solve it using Separation of Variables but first we create

## Dividing Fractions

There are 3 Simple Steps to Divide Fractions: Turn the second fraction (the one you want to divide by) upside down (this is now a reciprocal). Multiply the first fraction by that reciprocal of second fraction Simplify the fraction (if needed) Fractions and Whole Numbers What about division with fractions and whole numbers? Make the

## Determinant of Matrix: Minor – Cofactor & Sarrus Method, and Examples

Determinant of a matrix is a scalar value. It is calculated from square matrix. Its means that only matrix that has dimension 2×2, 3×3, 4×4, etc.  Determinant of matrix is used to solve some problem in mathematics. They are like system of linear equation, calculus problem, and especially invers matrix. If there is matrix A,

## Positive and Negative Numbers

Numbers Can be Positive or Negative – Negative sign + Positive sign No Sign Means Positive If a number has no sign it usually means that it is a positive number. Any numbers greater than zero are described as positive numbers. Usually, we don’t put a plus sign in front of positive numbers because the

## Irrational Numbers

Irrational means not Rational An Irrational Number is a real number that cannot be written as a simple fraction.   Example Rational Number 0.5 = ½ Irrational Number √2 = 1.414213562373095… = ?/? Rational Numbers A Rational Number can be written as a Ratio of 2 integers (ie a simple fraction). Irrational Numbers The numbers that