Answers

2015-06-30T16:54:46+05:30
(a+b)3 = a3 + b3 + 3ab(a+b)
as (a+b) = 12
so (a+b)3 = 12×12×12( 12 cube)
(a+b)3 = 1728
as we know
that (a+b)3 = a3 +b3+3ab(a+b)
putting the values
1728 = a3 + b3 + 3 ×30 ×12
1728 = a3 +b3 + 1080
1728 - 1080 = a3 + b3
there fore a3 + b3 = 648
hope i helped
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