# Thread: sin, cos, tan of terminal angles

1. ## sin, cos, tan of terminal angles

If the terminal side of an angle of t radians in standard position passes through the point (6,-8) then cos t = ___

If the terminal side of an angle of t radians in standard position passes through the point (-2,3) then tan t = ___

If the terminal side of an angle of t radians in standard position passes through the point (1.2,3.5) then sin t = ___

Answers would be nice, but explanation is key here! Test tomorrow and i don't understand this at all. Thanks in advance!

2. Originally Posted by keg
If the terminal side of an angle of t radians in standard position passes through the point (6,-8) then cos t = ___

If the terminal side of an angle of t radians in standard position passes through the point (-2,3) then tan t = ___

If the terminal side of an angle of t radians in standard position passes through the point (1.2,3.5) then sin t = ___

Answers would be nice, but explanation is key here! Test tomorrow and i don't understand this at all. Thanks in advance!
Hi keg,

Look at the attachments.

3. basic definition for the trig ratios of an angle in standard position whose terminal side passes through the point $(x,y)$ ...

$\cos(t) = \frac{x}{r}$

$\sin(t) = \frac{y}{r}$

$\tan(t) = \frac{y}{x}$

where $r = \sqrt{x^2+y^2}$