Sorry for not posting for such a long time. I have been busy with some schoolwork and i got sick.
This post is part of a series of posts on Trigonometry. To see all the posts, click on the tag #TrigonometryTutorials below. This is the post you should read before you read this.
Last time we talked about the new Definitions of the trig functions now that we know the unit circle.
is the co-ordinate reading of the unit circle, is the co-ordinate reading of the unit circle, and is the divided by
When you learnt co-ordinate geometry you learnt about quadrants
In Q I both and are positive, so sine, cosine, and tangent are all positive when is in QI.
In QII is negative but is positive, so in QII only sine is positive, and Cosine and Tangent are negative
In QIII both and are negative. Only Tangent is Positive as tangent is divided by the negatives are cancelled. Sine and Cosine are Negative in QIII
In QIV is negative but is positive, so in QIV only cosine is positive, and Sine and Tangent are negative