(0.5a + 0.16)^3 = (0.5a)^3 + 3(0.5a)^2(0.16) + 3(0.5a)(0.16)^2 + (0.16)^3= 0.125a^3 + 0.12a^2 + 0.048a + 0.004096
(0.5a + 0.16)^3 = (0.5a)^3 + 3(0.5a)^2(0.16) + 3(0.5a)(0.16)^2 + (0.16)^3
= 0.125a^3 + 0.12a^2 + 0.048a + 0.004096