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Find the approximate values of trigonometric functions for 31° without using a calculator or trigonometric tables.
Solution:
Is it possible to get the six trigonometric functions of 31° without using a calculator or trigonometric tables? Yes, we can. We can get the approximate values of trigonometric functions of 31° by approximation and error method.
We know that 30° is a special angle. The trigonometric functions for 30° are the following
Sin 30° = 1/2 Csc 30° = 2
Cos 30° = √3/2 Sec 30° = 2/√3
Tan 30° = 1/√3 Cot 30° = √3
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Note: All angles are converted from degrees into radians because radians are unitless and all trigonometric values are unitless.