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( 5 a + 3 b ) ^ { 3 } - ( 5 a - 3 b ) ^ { 3 } |
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Answer» (a+b)^3 =a^3 +b^3 +3ab (a+b)(a-b)^3 =a^3 -b^3 -3ab (a-b)(5a+3b)^3 =125 a^3 +27 b^3 +15ab (5a+3b)=125 a^3 +27 b^3 +75a^2 b+45a b^2........ (1)(5a-3b)^3 =125 a^3 -27 b^3 -15ab (5a-3b)=125 a^3 -27 b^3-75a^2 b+45ab^2......... (2)subtracting 2 from 1(5a+3b)^3 -(5a-3b)^3=54b^3+150a^2 b |
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