Răspuns:

3.

rad322, rad300, rad242, rad320, rad289, rad207

rad207<rad242<rad289<rad300<rad320<rad322

4.

5/4 × 3/20 - 1/3 × 9/10 + 5/18 × 18/10 =

3/16 - 3/10 + 1/2 =

(15-24+40)/80 =

31/80

5.

a) 2^3 × 3^7 × 6^5 = 2^3 × 3^7 × 2^5 × 3^5 = 2^8 × 3^12 pătrat perfect (toate puterile pare sunt pătrate perfecte)

rad(2^8 × 3^12) = 2^4 × 3^6

b) 1+2+3+...+288 = (288×289)/2 = 144 × 289 pătrat perfect =>radical = 12×17 = 204

c) 140×n pătrat perfect

???

d) 5^(2n) × 3^(2n+2) × (5 + 11) =

5^2n ×3^(2n+2) × 2^4 pătrat perfect