A chord 10 cm long is drawn in a circle whose radius is 5√2 cm. Find the areas of both the segments. [Take π = 3.14.]


 


Consider the figure shown above.


 


In this, the triangle AOB is an isosceles triangle. So here we will construct a perpendicular bisector from O on AB and as this triangle is isosceles therefore this perpendicular will also act as median and angle bisector.


 


Therefore,


 



 


Draw a perpendicular bisector from O which meets AB at D and bisects AB, as ABO is an isosceles triangle therefore OD acts as a median.


 


So, consider right angle triangle AOD right angled at D


 



 


Let AOD = θ Perpendicular = AD and Hypotenuse = AO = R


 


Given Radius of circle = R = 5√2 cm


 


Length of chord AB = 10 cm, AD = 5 cm


 



 



 



 



 


θ = 45°


 


AOD = 45°


 



 


Area of minor segment = Area of sector – Area of right angle triangle


 


eqn1


 



 


Where R = radius of the circle and θ = central angle of the sector


 



 



 



 


Area of sector = 39.25 cm2


 


Area of right angle triangle = 1/2 × base × height


 


As this is isosceles right-angle triangle


 


height = base = 5√2 cm


 


Area of right angle triangle = 1/2 ×5√2×5√2 = = 25 cm2


 


Put the value of area of sector and area of right angle triangle in equation 1,


 


Area of minor segment = 39.25 -25


 


= 14.25 cm2


 


Area of major segment = πR2 – area of minor segment


 



 



 


Area of major segment = 157 – 14.25 = 142.75 cm2


 


Area of major segment is 142.75 cm2 and of minor segment is 14.25 cm 2.


 

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