Question
If, ( a + b = 10 ) and ( a² + b² = 58 ), then find the
value of (a³ + b³).ÂSolution
(a + b = 10)
((a + b) ² = 10²)
( a² + b² + 2ab = 100)
( 58 + 2ab = 100)
( 2ab = 42 ab = 21)
(a³ + b³ = (a + b)(a²+ b² - ab) ) = 10 (58 - 21) = 10 * 37 = 370 )
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