IMPORTANT FORMULA.
1. Latitude = distance x cos θ 2. Departure = distance x sin θ
3. Distance = 2 2 ) ()( depart latit
4. Angle = tan-1 depart
latit
Triangulation
1. c² = a² + b² - 2ab cos C
2. area = C absin 2 1
3. area = ) )()(( c sbsass
s= 2 a+b+c
2
4. sin A = sin B
a b
Road secant
a = bearing BA - bearing BC
2
θ = bearing AD – bearing AE
cot α = L1 cosesθ -cot θ
L2
TREE DISTANCE AND TREE POINT PROBLEMS.
BC(AB+BC+CD) = sin b(sin a + sin b + sin c )
(AB)(BC) (sin a) (sin c)
tan Φ = a sin q
b sin p
tan x-y =tan (Φ - 45o) tan ( x+y )
2 2





