# Given the point #P(sqrt3/2,-1/2)#, how do you find #sintheta# and #costheta#?

##### 2 Answers

#### Explanation:

Coordinate of P:

Since t is in Quadrant 4, then, sin t is negative

Since

#### Explanation:

In this problem we're only asked for

Students should recognize immediately **The Two Tired Triangles of Trig.** Trig mostly only uses two triangles, namely **30/60/90,** whose sines and cosines in the various quadrants are **45/45/90,** whose sines and cosines are

Two triangles for a whole course is really not that much to memorize. Rule of thumb:

None of that mattered for this particular problem so I'll end my rant here.