Question

(1 point) Given cot(𝛼)=−21√2 and 𝜋/2<𝛼<𝜋, find the exact values of the remaining five trigonometric functions.

Note: You are not allowed to use decimals in your answer.

Answer 1

draw your triangle in standard position. Since cot𝛼 = x/y, you have

x = -21√2
y = 1
so, since r^2 = x^2+y^2, r = √883
Now the rest is easy, since
sin𝛼 = y/r
cos𝛼 = x/r,
and so on.

Why do I suspect a typo? Could it be that cot𝛼 = 2/√2 = -√2 ?
If so, then fix the values for y and r, and do the calculations accordingly.