Mathematics Question and Solution
a = ⅓(90)
a = 30°
sin30 = b/4
b = 2 cm.
sin60 = c/4
c = 2√(3) cm.
d = √(4²-2²)-√(4²-(2√(3))²)
d = √(12)-√(4)
d = (2√(3)-2) cm.
d = 1.4641016151 units.
Area Blue is;
Area trapezoid with parallel sides 2 cm and 2√(3) cm respectively and height (2√(3)-2) cm + Area sector with radius 4 cm and angle 30° - Area triangle with height 4 cm and base 4sin30 cm.
= (½*(2+2√(3))*(2√(3)-2))+(30π*4*4/360)+(½*4*4sin30)
= (½*8)+⅓(4π)-4
= 4+⅓(4π)-4
= ⅓(4π) square units.
