Question

De la ex 7 (a,b,c,d)

Answer 1

$7) \\ \\ a)2 \times (3 \sqrt{2} - \sqrt{3}) + 4 \times ( \sqrt{3} - \sqrt{2}) = \\ \\ 6 \sqrt{2} - 2 \sqrt{3} + 4 \sqrt{3} - 4 \sqrt{2} = \\ \\ (6 \sqrt{2} - 4 \sqrt{2}) + ( - 2 \sqrt{3} + 4 \sqrt{3}) = \\ \\ 2 \sqrt{2} + 2 \sqrt{3}$

$b)4 \sqrt{7} + 6 \sqrt{5} - 3 \times (2 \sqrt{5} - \sqrt{7}) = \\ \\ 4 \sqrt{7} + 6 \sqrt{5} - 6 \sqrt{5} + 3 \sqrt{7} = \\ \\ 4 \sqrt{7} + 3 \sqrt{7} = \\ \\ (4 + 3) \sqrt{7} = \\ \\ 7 \sqrt{7}$

$c)5 \sqrt{2} \times (3 - \sqrt{3}) + 4 \sqrt{6} - 6 \sqrt{2} = \\ \\ 15 \sqrt{2} - 5 \sqrt{6} + 4 \sqrt{6} - 6 \sqrt{2} = \\ \\ (15 \sqrt{2} - 6 \sqrt{2}) + ( - 5 \sqrt{6} + 4 \sqrt{6}) = \\ \\ 9 \sqrt{2} - \sqrt{6}$

$d) \sqrt{45} + 2 \times ( \sqrt{5} - 3) + 7 = \\ \\ 3\sqrt{5} + 2 \sqrt{5} - 6 + 7 = \\ \\ (3 \sqrt{5} + 2 \sqrt{5}) + ( - 6 + 7) = \\ \\ 5 \sqrt{5} + 1$

Answer 2

Răspuns

a. 2√2 + 2√3

b. 7√7

c. 9√2 - √6

d. 5√5 + 1

Explicație pas cu pas:

a. 2* (3√2 - √3) + 4* (√3 - √2) = 6√2 - 2√3 + 4√3 - 4√2 = 2√2 + 2√3

b. 4√7 + 6√5 - 3 * (2√5 - √7) = 4√7 + 6√5 - 6√5 + 3√7 = 7√7

c. 5√2 * (3 - √3) + 4√6 - 6√2 = 15√2 - 5√6 + 4√6 - 6√2 = 9√2 - √6

d. √45 + 2* (√5 - 3) + 7 = 3√5 + 2√5 - 6 + 7 = 5√5 + 1