212 PRACTICAL MATHEMATICS 



For the area B, V OY = TT \x z dy 



r 4 



= TWO x n+l dx, since dy = nax n+l dx 



J2 



2 

 TT x M37 x 2-273 



_ 



3-137 



= 177-5 . 

 For the area A, V OY = TT x 11 x 4 2 - TT x 5 x 2 2 TT p 2 dy 



= 1767C - 207C - 177-5 



= 312-6 

 For the area B, V ox = TC x 4 x II 2 - TT x 2 x 5 2 TC U 2 <r 



= 4847T - 507t - 415-9 



= 947-1 



Finally for the area A, x = 



312-6 



27T x 15-92 

 = 3-126 



415-9 

 ~ 2 TC x 15-92 



= 4-159 



y 



and for the area B, x = ^ 



177-5 



27T x 18-08 

 = 1-563 

 Vox 



947-1 



27T x 18-08 

 = 8-335 



