a) $-\sqrt{81}=-9$
b) $\sqrt{225}=15$
c) $\sqrt{\frac{64}{25}}=\frac{8}{5}$
d) $\sqrt{(-11)^{2}}=11$
e) $\sqrt{(13)^{2}}=13$
Bài 4. Tính
a) $-\sqrt{81}$
b) $\sqrt{225}$
c) $\sqrt{\frac{64}{25}}$
d) $\sqrt{(-11)^{2}}$
e) $\sqrt{(13)^{2}}$
a) $-\sqrt{81}=-9$
b) $\sqrt{225}=15$
c) $\sqrt{\frac{64}{25}}=\frac{8}{5}$
d) $\sqrt{(-11)^{2}}=11$
e) $\sqrt{(13)^{2}}=13$