Question

(6-корень из 5)(2+7корень из 5

Answer 1

$(6-\sqrt{5})(2+7\sqrt{5})=12+42\sqrt{5}-2\sqrt{5} -7=5+40\sqrt{5} =\sqrt{5} (\sqrt{5} +40)$

Answer 2

To simplify the expression (6-корень из 5)(2+7корень из 5), first let's understand what "корень из" means. In Russian, "корень из" translates to "square root of." So, the expression can be rewritten as:

(6-√5)(2+7√5)

To simplify it further, we can use the distributive property:

(6-√5)(2+7√5) = 62 + 67√5 - √52 - √57√5

Now, simplify each term:

12 + 42√5 - 2√5 - 7√(5*5)

12 + 40√5 - 7√25

Since √25 = 5, we have:

12 + 40√5 - 7*5

12 + 40√5 - 35

Finally, combine like terms:

(12 - 35) + 40√5

-23 + 40√5

So, the simplified expression is: -23 + 40√5