Mathematics Question and Solution
Let the square side be 2 units.
a = √(2²+1²)
a = √(5) units.
b = atan(2)°
c = atan(½)°
d² = 8-8cos150
d = 3.86370330516 units.
e = 0.5d
e = 1.93185165258 units.
f = 90-15-atan(½)
f = 48.43494882292°
g² = 5+1.93185165258²-2√(5)*1.93185165258cos48.43494882292
g² = 3
g = √(3) units.
(√(3)/sin48.43494882292) = (1.93185165258/sinf)
f = 56.56505117716°
Therefore the required angle alpha is;
180-56.56505117716-atan(2)
= 180-120
= 60°
