SOLUTION: As θ increases from pi/2 to pi radians, which of the following is true? cosθ increases from 0 to 1. tanθ decreases. sinθ decreases from 1 to 0. sin

Algebra ->  Trigonometry-basics -> SOLUTION: As θ increases from pi/2 to pi radians, which of the following is true? cosθ increases from 0 to 1. tanθ decreases. sinθ decreases from 1 to 0. sin      Log On


   

Question 619876: As θ increases from pi/2 to pi radians, which of the following is true?


cosθ increases from 0 to 1.
tanθ decreases.
sinθ decreases from 1 to 0.
sinθ increases from 0 to 1.
None of these is correct.

the answer is the third one, but I dont understand why. I thought the first two were also correct?
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
As θ increases from pi/2 to pi radians, cosθ decreases from 0 to negative 1.
Have a look at the unit circle and you'll see that the x coordinates are negative here.
So choice A is false.


As θ increases from pi/2 to pi radians, tanθ increases.
Again use the unit circle to see this.
So choice B is false.