Question

Fie numarul x =3(1+2+3+...+49)+1225,atunci valoarea lui√x este........

Answer 1

x = 3(49*50/2) + 1225 = 3 * 49 *25 + 1225 = 25(3 * 49 + 49) = 25 * 49 * (3 + 1) = 25 * 49 * 4 = 5² * 7² * 2²

=> √x = 5 * 7 * 2 = 70

Answer 2

1+2+3+...+49=49x50/2=1225

x=3x1225+1225

x=3675+1225

x=4900

√4900=70