The locations, given in polar coordinates, for two planes approaching an airport are (4 mi, 12º) and (3 mi, 73º). Find the distance between the two planes.
To get the distance between the two planes we use the cosine rule; c^2=a^2+b^2-2abCosC thus;' a=4 miles b=3 miles C=73-12=61 thus c^2=4^2+3^2-2*3*4Cos 61 c^2=16+9-24cos61 c^2=25-24cos61 c^2=13.3646 c=sqrt13.3646 c=3.66 miles They two planes are 3.66 miles apart
