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Algebra 15m+17n=21 ,17m+15n=11 |
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Answer» Step-by-step explanation: (a + B) 2 = a 2 + b 2 + 2ab (a − b) 2 = a 2 + b 2 − 2ab a 2 − b 2 = (a − b) (a + b) (x + a) (x + b) = x 2 + (a + b) x + ab (a + b + c) 2 = a 2 + b 2 + c 2 + 2ab + 2bc + 2ca (a + (−b) + (−c)) 2 = a 2 + (−b) 2 + (−c) 2 + 2A (−b) + 2 (−b) (−c) + 2a (−c) (a – b – c) 2 = a 2 + b 2 + c 2 − 2ab + 2bc − 2ca (a + b) 3 = a 3 + b 3 + 3AB(a + b) (a − b) 3 = a 3 - b 3 - 3ab(a - b) a 3 − b 3 = (a − b) (a 2 + b 2 + ab) a 3 + b 3 = (a + b) (a 2 + b 2 − ab) (a + b + c) 3 = a 3 + b 3 + c 3 + 3(a + b)(b + c)(c + a) a 3 + b 3 + c 3 − 3ABC = (a + b + c) (a 2 + b 2 + c 2 − ab − bc − ac) If (a + b + c) = 0, a 3 + b 3 + c 3 = 3abc |
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