Quick Trig question: How would I round my answer correctly?
I got the answer cot=2√ 5/5

which is totally different from the answer I suppose to get.
-------------------------------------------------------

answers:
Captain Matticus, LandPiratesInc say: cos(t) = 2/3

cot(t) = cos(t) / sin(t)
cot(t)^2 = cos(t)^2 / sin(t)^2
cot(t)^2 = cos(t)^2 / (1 - cos(t)^2)
cot(t)^2 = (2/3)^2 / (1 - (2/3)^2)
cot(t)^2 = (4/9) / (1 - 4/9)
cot(t)^2 = (4/9) / (5/9)
cot(t)^2 = 4/5
cot(t) = 2 / sqrt(5)
cot(t) = 2 * sqrt(5) / 5

Go with 2 / sqrt(5) instead of rationalizing the denominator.
-
electron1 say: Cotangent = base ÷ height

2 is the base of the right triangle. 3 is the hypotenuse of the right triangle. Let’s use the following equation to determine the height of the triangle.

2^2 + Height^2 = 3^2
Height^2 = 5
Height = √5

Cotangent = base ÷ height = 2 ÷ √5

I hope this is helpful for you.
-
Φ² = Φ+1 say: cosθ = 2/3
tanθ = √(3²-2²) / 2 = √5 / 2
cotθ = 2/√5
-