Trigonometry Angles--Pi/2 -- From Wolfram MathWorld

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Trigonometry Angles--Pi/2 DOWNLOAD Mathematica NotebookDownload Wolfram Notebook TrigonometryAnglesPi2

By the definition of the functions of trigonometry, the sine of pi/2 is equal to the y-coordinate of the point with polar coordinates (r,theta)=(1,pi/2), giving sin(pi/2)=1. Similarly, cos(pi/2)=0, since it is the x-coordinate of this point. Filling out the other trigonometric functions then gives

cos(pi/2)=0 (1)
cot(pi/2)=0 (2)
csc(pi/2)=1 (3)
sec(pi/2)=infty (4)
sin(pi/2)=1 (5)
tan(pi/2)=infty. (6)

See also

Digon, Trigonometry Angles, Trigonometry, Tusi Couple

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Cite this as:

Weisstein, Eric W. "Trigonometry Angles--Pi/2." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/TrigonometryAnglesPi2.html

Subject classifications

  • Geometry
  • Trigonometry
  • Trigonometric Identities
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