How would you find the exact value of the six trigonometric function of 225 degrees?

1 Answer
Alan P.
Nov 21, 2016

sin(225^@)= -1/sqrt(2)color(white)("XXX")csc(225^@)=-sqrt(2)
cos(225^@)= -1/sqrt(2)color(white)("XXX")sec(225^@)=-sqrt(2)
tan(225^@)=+1color(white)("XXXX")csc(225^@)=-1

Explanation:

225^@=180^@+45^@

So 225^@ has a reference angle of 45^@ in Quadrant 3 (Q III).

According to CAST,
only tan (and its inverse cot) are positive in Q III.

45^@ is one of the standard trigonometric angles.
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