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)

Exact values and radians

• All of the above applies to radians as well as degrees
• Here is a table of all exact values including?radians?(see Radian Measure)

How do I find exact values of other angles?

• 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