Given sin = in quadrant III, tan = in quadrant II; find the value of sin( + ):
I've posted my solution -- which the answer key says is wrong -- here, http://imagebin.ca/img/tnINM0J.png .
Please tell me what I'm doing wrong.
Given sin = in quadrant III, tan = in quadrant II; find the value of sin( + ):
I've posted my solution -- which the answer key says is wrong -- here, http://imagebin.ca/img/tnINM0J.png .
Please tell me what I'm doing wrong.
Hello, beardedoneder!
Sorry, I couldn't read your work.
Given: .
find the value of: .
We have: .
is in a right triangle with:
Pythagorus says: .
. . In Quadrant III:
Hence: . .[1]
We have: .
is in Quadrant II with:
Pythagorus says: .
Hence: . .[2]
We want: .
Substitute [1] and [2]: