Edexcel IGCSE Maths 复习笔记 4.3.1 Bearings & Scale
What are bearings?
- Bearings (sometimes referred to as three-figure bearings) are a way of describing and using angles
- The way they are defined means it gives us a precise location and/or direction which means they have good uses in navigation
What do I need to know?
Bearings have 3 rules:
- They are measured from the North directionNorth is usually straight up in terms of a scale drawing or map drawn on a piece of paper and should be shown somewhere on the diagram
- They are measured clockwise (from North)If you get muddled up look at a clock on the wall
- The angle should always be written (said) with 3 figuresSo angles under 100° should have zeros to start, eg 059, 008
Notice also that the degree symbols are not usually included when talking about bearings
Make sure you have all the equipment you need for your maths exams, along with a spare pen and pencil. Rubber and pencil sharpener can be essential on these questions as they are all about accuracy. Make sure you have compasses that aren’t loose and wobbly, make sure you can see and read the markings on your ruler and protractor.