# Math Help - Great Circles

1. ## Great Circles

Great Circles!

Use the points:

C
( 40 N , 70 W )
D ( 40 N , 150 W )E( 70 N , 150 W ) F ( 70 N , 70 W )

to find the distance from C to E along a great circle.

( Hint: You will need to find the lengths of the Trapezium CDEF)

Any Contribution and Help will be Appreciated.

Thanks!!!

2. Are you familiar with the Haversine formula?.

Let lat1=u, long1=v, lat2=x, long2=y

$cos^{-1}\left(cos(u)cos(v)cos(x)cos(y)+cos(u)sin(y)cos(x )sin(y)+sin(u)sin(x)\right)$

Multiply this by the radius of the Earth and it should get you close.