Question

tem com vcs me ajudar nessa questao​

Answer 1

1) B

2) C

3) C

4) C

1)

$x \times y = \\ {10}^{2} \times ( \frac{2}{5} ) {}^{ - 2} = \\ 100 \times \frac{25}{4} = \\ 25 \times 25 = 625$

2)

$\sqrt{ab + c} = \\ \sqrt{4 \times 30 + 8} = \\ \sqrt{120 + 8} = \\ \sqrt{128} = \\ 8 \sqrt{2}$

3) I.

$\sqrt{6} + \sqrt{75} + \sqrt{3} = \\ 2 \sqrt{3} + 5 \sqrt{3} + \sqrt{3} = \\ 8 \sqrt{3}$

II.

$\sqrt{12} \times \sqrt{3} = \\ \sqrt{36} = 6$

III.

$\sqrt[3]{27} = 9 \\ \sqrt[3]{ {3}^{3} } = 9 \\ 3 = 9 \: \: \: falso$

IV.

$\frac{11}{ \sqrt{11} } = \frac{11 \times \sqrt{11} }{ \sqrt{11} \times \sqrt{11} } = \frac{11 \sqrt{11} }{11} = \sqrt{11}$