問題
次の値を求めよ.
解説
- (1) $\sqrt{27}$
- $=\sqrt{9\cdot3}=3\sqrt{3}=$$3\sqrt{3}$
- (2) $\sqrt{0.0049}$
- $=\sqrt{\dfrac{49}{10000}}=\dfrac{7}{100}=$$0.07$
- (3) $\sqrt{\dfrac{75}{16}}$
- $=\dfrac{\sqrt{75}}{4}=$$\dfrac{5\sqrt{3}}{4}$
- (4) $\left(-\sqrt{5}\right)^{2}$
- $=$$5$
- (5) $\sqrt{(-8)^{2}}$
- $=\sqrt{64}=$$8$
- (6) $\sqrt{(-8)(-2)}$
- $=\sqrt{16}=$$4$
- (7) $\sqrt{5}\,\sqrt{20}$
- $=\sqrt{100}=$$10$
- (8) $\sqrt{12}\,\sqrt{18}$
- $=\sqrt{216}=\sqrt{36\cdot6}=$$6\sqrt{6}$
- (9) $\dfrac{\sqrt{24}}{\sqrt{3}}$
- $=\sqrt{8}=$$2\sqrt{2}$
