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The sign of Trigonometric ratios and reference angles

This is one of the main principles behind using the trigonometric functions and inverse trigonometric functions for any angle. The absolute value of the x coordinate can replace the Adjacent side and the y coordinate can replace the Opposite side of a rig

Move the slider to change the Standard angle and observe:
  • a triangle with sides labeled for trigonometric functions
  • the Reference angle in each corresponding quadrant
  • The values of trigonometric functions for both reference and standard angles in each quadrant.
How do the signs of the trigonometric functions vary in the different quadrants?