Giải Bài 6.1 trang 7 SBT Toán 11

Lời giải

a) $\sqrt[3]{-27} = \sqrt[3]{(-3)^3} = -3$.

b) $25^{\frac{3}{2}} = \left(5^2\right)^{\frac{3}{2}} = 5^{2\cdot\frac{3}{2}} = 5^3 = 125$.

c) $32^{-\frac{2}{5}} = \left(2^5\right)^{-\frac{2}{5}} = 2^{5\cdot\left(-\frac{2}{5}\right)} = 2^{-2} = \dfrac{1}{4}$.

d) $\left(\dfrac{27}{8}\right)^{\frac{2}{3}} = \left[\left(\dfrac{3}{2}\right)^3\right]^{\frac{2}{3}} = \left(\dfrac{3}{2}\right)^{3\cdot\frac{2}{3}} = \left(\dfrac{3}{2}\right)^2 = \dfrac{9}{4}$.

Đáp số