Find sin θ if cot θ = - 2 and cos θ < 0

Given was cotθ=−21 and cot is the reciprocal of tan
therefore 
tanθ=1−2
solve for the hypotenuse c since t he opposite side a=1 and the adjacent sides b=−2 were already given. that is,
c2=a2+b2
c=√(1)2+(−2)2
c=√5

Solving for sinθ

sinθ=oppositesideshypoteνse=ab

sinθ=1√5 need to rationalize
sinθ=(1√5)×√5√5

sinθ=√55

Note that the adjacent side of the angle is −2 so the angle
θ is found in the 2nd quadrant.

the correct answer is d

hope this

entering that problem on the tube might get you an answer