We can find an unknown angle in a right-angled triangle, as long as we know the lengths of two of its sides. Use Sine, Cosine or Tangent! Use SOHCAHTOA to help you, like this: How to Finding an Angle in a Right Angled Triangle 1. find the names of the two sides we know Adjacent … Continue reading "Finding an Angle in a Right Angled Triangle"

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## Complex Numbers

Imaginary number Imaginary number (when squared give a negative result) i is the unit of imaginary number which is square root of -1 i = √-1, because i2=-1 So, (7i)2 = -7 Definition of Complex Number A Complex Number is a combination of a Real Number and an Imaginary Number Either Part Can Be Zero … Continue reading "Complex Numbers"

Read More## Directly and Inversely Proportional

Directly Proportional Directly proportional: when one amount increases, another amount increases at the same rate. The symbol for “directly proportional” is ∝ Inversely Proportional Inversely Proportional: when one value increases, at the same rate that the other decreases. Examples Directly Proportional Inversely Proportional Have more workers You pay more Work time is shorter How … Continue reading "Directly and Inversely Proportional"

Read More## Irregular Polygon

Regular polygon is a polygon that has all angles equal and all sides equal. So, regular polygon has a = b = c = d = e, and ∠v = ∠w =∠x = ∠y = ∠z Definition of Irregular Polygon Irregular polygon is a polygon that does not have all sides equal and all angles … Continue reading "Irregular Polygon"

Read More## Decimals, Fractions, and Percentages

Definition Decimals, Fractions & Percentages are different ways of showing value Examples Percent Decimal Fraction 1% 0.01 1/100 5% 0.05 5/100 10% 0.1 10/100 25% 0.25 25/100 50% 0.5 50/100 75% 0.75 75/100 100% 1 100/100 125% 1.25 125/100 150% 1.5 150/100 200% 2 200/100 Conversions Base Form Decimals Fractions Percentages Decimals – 1) multiply … Continue reading "Decimals, Fractions, and Percentages"

Read More## Angles of Elevation & Depression

Angles of Elevation Angle of elevation is the angle from the horizontal upward to an object. An observer’s line of sight would be above horizontal line. The angle of elevation is angle formed by a horizontal line & line of sight up to an object when the object is above the line. When you see … Continue reading "Angles of Elevation & Depression"

Read More## Set-Builder Notation

A Set is a collection of things (often numbers). Example: {2, 3, 5} is a set. Here is a simple example of set-builder notation: General Form: {formula for elements: restrictions} or {formula for elements| restrictions} Show the Type of Number You can show what type of number x is. Number Types Symbols Details N Natural Numbers … Continue reading "Set-Builder Notation"

Read More## Translation

Definition Translation means Moving without rotating, resizing or anything else, just moving. To Translate a shape Every point of the shape must move: the same distance in the same direction. Learn More Angles Acute Angles Obtuse Angles Supplementary Angles Geometry Index

Read More## Acute Angles

An Acute Angle is less than 90° More Examples of Acute angles Which Angle? Remember to look carefully at which angle you are being asked to name. The acute angle is the small angle which is less than 90°. The larger angle you will have a Reflex Angle (more than 180° but less than 360°) … Continue reading "Acute Angles"

Read More## Differentiable

Definition of Differentiable Differentiable means: the function has derivative the derivative f’(x) must exist for every value in the function’s domain Examples The use of differentiable function When a function is differentiable, we can use all the power of calculus when working with it. When a function is differentiable, it is continuous. Differentiable ⇒ Continuous … Continue reading "Differentiable"

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