Arun
Last Activity: 7 Years ago
a+b = 11 and,a²+b²=65 so ,(a+b)² = a²+b²+2ab , Put 11 in a+b and 65 in a²+b² to get ab(11)²= 65 + 2ab121 = 65 + 2ab2ab = 56ab = 28Put the value of ab in :a³+b³ = (a+b)³ - 3ab( a+b) = (11)³ - 3×28(11) = 1331 - 924 = 407