Hi, I am working on the following problem and do not understand why the final answer is slightly different than my answer:
If cos t = ( - 1/3 ) and ( (pi/2) < t < pi )
Compute sin ( -t ) + cos ( -t )
I find sin t to be ( 2 (sqrt 2) / 3 ) using the pythag. theorem.
sin ( -t ) = - sin t... this makes 2 (sqrt 2) / 3 a negative value
cos ( -t ) = cos t... this leaves the negative value of ( - 1/3 )
I then combine over the denominator of 3:
( - 2 (sqrt 2) - 1 ) / 3
The answer in the book is - (( 2 (sqrt 2) + 1) / 3 )
I know if I distribute the negative, I'll end up with the same answer, but why is the negative pulled to the front of the answer?