3. 3√5 = √9*√5 = √45
4. ... = 0,2*3√3 - 1,5*7√3 + 0,8√3 = √3*(0,6-1,5+0,8) = -0,1*√3
5. ... = √7*√b*(√7-√b)
6. ... = (8*√22)/22 = (4*√22)/11
7. ... = √42 и √35. Первый корень больше второго.
8. ... = ((46*(4-2√3) - 12*(5-√2) ) / ((5-√2)*(4-2√3))) - 2√2 + 3√12 = ((184-92√3-60+12√2) / (20-10√3-4√2+2√6)) - (2√2 - 6√3)*(20-10√3-4√2+2√6) = ((124-92√3+12√2)/(20-10√3-4√2+2√6)) - ((40√2-20√6-16+8√3-120√3+180+24√6-36√2))/(20-10√3-4√2+2√6)) = (124-92√3+12√2-40√2+20√6+16-8√3+120√3-180-24√6+36√2)/(20-10√3-4√2+2√6) = (-40+20√3+8√2-4√6)/(20-10√3-4√2+2√6) = -2