Hi

In 13.1,5 sum I have two doubts please clarify

1. When we cut the hemisphere from one side of the cube, why we are taking the total surface area 6a

2. Why we have to subtract base area of the hemisphere.

As per knowledge

Area of the remaining solid= 5a 2 + csa of Hemisphere

= 5a 2 + 2πr

= 5a 2 + 2π(a/2) 2

= 5a 2 + πa 2 /2

= a 2 (5 + π /2)

 

Or

Area of the remaining solid= 6a 2  - tsa of Hemisphere

= 6a 2  - 3πr2  

= 6a 2  - 3π(a/2) 2

= 6a 2  - 3πa 2 /4

= a 2 (6 - 3π /2)

 

So please clear my doubt

 

Thank you

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