A. $\sqrt{(2.1-0.3)^{2}}$ = 1.341...
B. $\sqrt{1.21}$= 1.1
C. $\frac{\sqrt{121}}{10}$=1.1
D.$ \sqrt{(0.7+0.4)\times(1.3-0.2)}$=1.1
Đáp án: A
A. $\sqrt{(2.1-0.3)^{2}}$ = 1.341...
B. $\sqrt{1.21}$= 1.1
C. $\frac{\sqrt{121}}{10}$=1.1
D.$ \sqrt{(0.7+0.4)\times(1.3-0.2)}$=1.1
Đáp án: A