Between N75E and E there are (90-75)=15° Between E and S there are 90° Between South and S12°W there 12° Applying cosine rule Another way is to measure all angles clockwise from north (called azimuth) The ship at S12°W is at 180+12 = 192° <span>The ship at N75°E is at 75° </span> <span>Angle between them is 192-75 = 117° </span> Applying cosine rule: c=√(36²+24²-2×36×24cos117) c=√2656.496 c=51.54 mi
Notice that for any increase, x * l or x * r, in length or radius, the increase in surface area is x squared (x2) and the increase in volume is x cubed (x3).