U1+u2+u3+u4 = 30 , u1^2+u2^2+u3^2+u4^2 =340 tentukan nilai u1^3 +u2^3+u3^3+u4^3
U1 + U2 + U3 + U4 = 30
U2 + U3 = 30/2 = 15
kemungkinan : U2 = 7
U3 = 8
beda = 1
maka U1 = 6
U3 = 9
U1³ + U2³ + U3³ + U4³
= 6³ + 7³ + 8³ + 9³
= 216 + 343 + 512 + 729
= 1.800