|a-2|+(b-3)^2=0
|a-2|和(b-3)^2都≥0
∴a-2=0 a=2
b-3=0 b=3
x^(2a+3)*x^(b-2)*x^(ab)
=x^(2a+3+b-2+ab)
=x^(4+3+6+1)
=x^14