Question: `b - [b - (a + b) - {b - (b - a - b)} + 2a]`
A
`2b`
B
`a - b`
C
`a + b`
D
None of these
Note: Given Exp ,
`= b - [b - (a + b) - {b - {b - bara - b)} + 2a]`
`= b - [b -a - b - {b - (b - a + b)} + 2a]`
`= b - [-a - {b - 2b + a + 2a}]`
`= b - [- a - {- b + 3a}]`
`= b - [ -a + b - 3a]`
`= b - [- 4a + b]`
`= b + 4a -b`
`= 4a`.