Posts Tagged ‘expression’
Thursday, December 24th, 2009
Finding the Function of a Directed Graph
Description
A detailed tutorial on finding the function of a directed graph. Step by step tutorial including several examples of finding functions of digraphs for reference.
Overview
A directed graph, more commonly known as a digraph, is the visual representation of a function or of a relation. As in any graph, there are points and lines – called vertices and edges in a digraph. Each edge has an arrow pointing to a vertex. The first vertex – the one the arrow comes from – is the x coordinate of an ordered pair. The second vertex – the one the arrow is pointing to – is the y coordinate of an ordered pair. In the case of double-sided arrows, two ordered pairs are made, with the x and y coordinates switching. This is done for every single vertex and edge on the graph.
Tags: arrow, coordinate. ordered, digraph, directed, discrete math, double, edges, expression, First, function, graph, lines, pair, points, relation, representation, second, side, vertex, vertices, visual, x, y
Posted in Discrete Math | No Comments »
Thursday, December 10th, 2009
Overview of Two-Way Counting
Description
A detailed tutorial on two-way counting. Step by step tutorial including several examples of two-way counting for reference.
Overview
Two-way counting is when any expression for a given quantity are determined using two different counting approaches. Many people believe that a quadratic equation is the perfect example of two-way counting, because you find the quantity in more than one way. However, this is incorrect. Two-way counting is actually a backwards method – you have the quantity already, you just need to figure out how you could get it. This is used often in combinations and permutations, where you often already know what quantity you need to have, you just have to figure out how to get there.
Tags: binomial, combination, counting, equation, example, expression, method, permutation, quadratic, quantity, statistics, two, two-way, way
Posted in Statistics | No Comments »
Friday, November 20th, 2009
How to Pick Variables
Description
A detailed tutorial on how to pick variables. Step by step tutorial including several examples of how to pick variables for reference.
Overview
Variables are letters picked to represent unknown values in expressions and equations. Usually they are lowercase, but they can be made uppercase. When trying to pick a variable, you must choose wisely. x is the most common variable, followed by n. x is picked because people associate it with the unknown, and n is picked because it stands for “number.” The variable should be easily recognizable – you should not use a variable that looks like another number or some symbol of a mathematical operation. You should check to see what is included in your equation – for instance, m stands for slope, so if you are doing an equation with slope you need to pick a different variable to avoid confusion. And you should always pick a variable that makes sense – the first letter of your subject matter usually works quite well.
Tags: a, algebra, b, c, choose, equation, expression, lowercase, m, mathematical, n!, number, operation, slope, symbol, unknown, uppercase, value, variable, variables, x, y, z
Posted in Algebra | No Comments »
Thursday, November 12th, 2009
Zero Pairs Explained
Description
A detailed tutorial on zero pairs. Step by step tutorial including several examples of how to solve equations using zero pairs for reference.
Overview
Zero pairs are a method of adding and subtracting integers, and simplifying expressions with addition and subtraction in them. A zero pair is any pair of numbers that when added or subtracted, equal zero. Based on this definition, the only numbers that can form a zero pair, besides two zeros, are a negative number n and a positive number n. When in equations, zero pairs can be cancelled out, therefore simplifying the expression. This is very useful when more complicated equations are given.
Tags: adding, arithmetic, cancelled, difference, equation, expression, integer, negative, number, pair, positive, simplification, simply, subtracting, sum, zero
Posted in Arithmetic | No Comments »
Thursday, November 12th, 2009
How to Solve Negative Exponents
Description
A detailed tutorial on how to solve negative exponents. Step by step tutorial including several examples of solving negative exponents for reference.
Overview
An exponent is a number representing how many times you multiply the base – the number the exponent is on – by itself. Which is why negative exponents are so confusing – how can you multiply something by itself a negative number of times? The easiest way to think of a negative exponent, is that if you take away the negative sign and put the base and exponent under the number 1 (like as a fraction), you are saying the same thing! A negative exponent simply needs to be moved to the denominator (or the numerator, if it is in the denominator) to make it a positive exponent. This can be tricky when there are other numbers or expressions found in the same fraction, but not impossible.
Tags: algebra, base, denominator, equation, exponents, expression, fraction, multiply, negative, numerator, positive, power
Posted in Algebra | No Comments »
Friday, October 2nd, 2009
Definition of the Index of a Radical Expression
Description
A detailed tutorial on the definition of the index of a radical expression. Step by step tutorial including several examples of the index of a radical expression for reference.
Overview
A radical expression is what most people know as a square root. The number, variable, or expression inside the square root symbol is referred to as the radicand. What some of you may not realize is that not only are there square roots, there are cube roots, and several other types of roots. These are the exact opposite functions of the exponents. A square root should technically have a little number two on the outside left of the square root symbol. A cube root would have a three there – any number can go there. That is the index.
Tags: arithmetic, cube root, exponent, expression, index, Math, radical, radicand, root, square root, symbol
Posted in Arithmetic | No Comments »
