If (a,b) is a point on the terminal side of angle t in standard position, then cos(t) equals:

Question

kj4uts · Answer

attachment

phi · Answer

plot the point.  (for example, assume (a,b) is in the first quadrant)
label the sides of a triangle with hypotenuse from (0,0) to (a,b)
the sides should have  length a for the x-axis,  length b for the vertical leg
use pythagoras to find the length of the hypotenuse 
(or the distance formula between the points (0,0) and (a,b) )
finally, write down the cosine  (SOH CAH TOA )
Cosine = adjacent / hypotenuse