∴a-2b+3=2，

∫B = 2a-B- 1√ 1- A cube root whose square is1-a.

∴2a-b- 1=3，

The simultaneous solution of the two formulas is: a=3, b=2,

∴A= radical number 3+3×2=3,

B= the square of the number of cubic roots 1-3 =-2,

∴A+B=3+(-2)= 1，

The square root of a+b is 1.