Exact values
In trigonometry some values of sin, cos and tan are “nice”
For example?sin 30° = ?,?tan 45° = 1
We can find those associated with the angles?30°,?45°?and?60°?using SOHCAHTOA on isosceles and equilateral triangles
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sin,?cos?and?tan?values for?30°,?45°?and?60°?should be recalled easily
Memorise either the actual values or how to work them out from the triangle
sin,?cos?and?tan?for?0°,?90°,?180°?should also be very familiar
They can be recalled using the relevant?trigonometric?graph?(see Graphs of Trigonometric Functions)
All of the above applies to radians as well as degrees
Here is a table of all exact values including?radians?(see Radian Measure)
Exact?sin,?cos?and?tan?values of?multiples?of?30°,?45°,?60°?can also be found
This is a combination of recalling the basic values and using the graph
Draw the triangles for?sin,?cos?and?tan?of?30°,?45°?and?60°?on the exam paper so that you can then use them as many times as you need throughout the paper.
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