formule de calcul prescurtat.pdf
DESCRIPTION
fhdg fjfnTRANSCRIPT
FORMULE DE CALCUL PRESCURTAT(a / b)2 = a2 / 2ab / b2
(a – b)2 = a2 – 2ab / b2
(a / b)(a – b) = a2– b2
(a / b / c)2 = a2 / b2 / c2 / 2(ab / bc / ca)(a / b)3 = a3 / 3a2 b / 3ab2 / b3
(a – b)3 = a3 – 3a2b / 3ab2 - b3
a3 / b3 = (a / b)(a2 – ab / b2)a3 – b3 = ( a – b)(a2 / ab / b2)
a2 / ab / b2 = (a / b)2 – aba2 – ab / b2 = (a / b)2 – 3ab
(a / b)3 = a3 / b3 / 3ab(a / b)(a – b)3 = a3 – b3 – 3ab(a – b)
(a/b/c/d)2 = a2/b2/c2 / d2 / 2(ab / ac / ad / bc/ bd / cd)(a/b/ c/d)2 = a2 / b2 / c2 / d2 / 2[(a / b)(c/ d) / ab / cd]
an – bn = ( a – b)(an-1 / an-2b / ... / abn-2 / bn-1)an / bn = ( a / b)(an-1 – an-2b / ... / abn-2 – bn-1) « n impar
an – 1= ( a – 1)(an-1 / an-2 / ... / a / 1)an / 1= ( a / 1)(an-1 – an-2 / ... / a – 1) « n impar
(ab / cd)2 / (ad – bc)2 = (a2 / c2)(b2 / d2)(a / b)(b / c)(c / a) = ab(a/b) / bc(b/ c) / ca(c/ a)/ 2abc(a/ b/c)(ab/bc /ca) = ab(a/b) / bc(b/c) / ca(c/a) / 3abc
(a – b)(b – c)(c – a) = ab(b – a) / bc(c – b) / ca(a – c)(a / b / c)3 = a3 / b3 / c3 / 3(a / b)(b / c)(c / a)
(a / b / c)3 = a3 / b3 / c3 / 3(a / b / c)(ab / bc / ca) – 3abc (a / b)4 = a4 / 4a3b / 6a2b2 / 4ab3 / b4
(a2 + ab + b2)(a2 - ab + b2) = a4 + a2b2 + b4