Question

Resolva:
a) 7 × [√ 1/49 - ( 3/5 + 2/5 )]
b) 4 × [√ 2,25 - (2 - √9)]​

Answer 1

a)

$= 7 \: . \: [ \sqrt{ \frac{1}{49} } - ( \frac{3}{5} + \frac{2}{5}) ] \\ = 7 \: . \: [ \frac{ \sqrt{1} }{ \sqrt{49} } - ( \frac{3 + 2}{5} )] \\ =7 \: . \: [ \frac{1}{7} - \frac{5}{5} ] \\ = 7 \: . \: [ \frac{1}{7} - 1] \\ = 7 \: . \: [ \frac{1 - 7}{7} ] \\ = 7 \: . \: [ - \frac{6}{7} ] \\ = - \backslash\!\!\!7 \: . \: \frac{6}{\backslash\!\!\!7} \\ \boxed{= - 6}$

b)

$= 4 \: . \: [ \sqrt{2,25} - (2 - \sqrt{9} )] \\ = 4 \: . \: [1,5 - (2 - 3)] \\ = 4 \: . \: [1,5 - ( - 1)] \\ = 4 \: . \: [1,5 + 1] \\ = 4 \: . \: 2,5 \\ \boxed{= 10}$

Att. NLE Top Shotta