[COLOR=DarkSlateGray][B]Function tauxx(c#, m1#, m2#, k#)
Application.Volatile 'Facultatif
Dim u0#, u1#, u2#, y0#, y1#, y2#
u1 = 0.1: y1 = c - m1 * (1 - (1 + u1) ^ -k) / u1 - m2 * (1 + u1) ^ -k
u2 = 0.05: y2 = c - m1 * (1 - (1 + u2) ^ -k) / u2 - m2 * (1 + u2) ^ -k
Do Until Abs(y2) < 0.0000000000001 Or y2 = y1
u0 = u1: u1 = u2: y0 = y1: y1 = y2
u2 = u0 - y0 * (u1 - u0) / (y1 - y0): y2 = c - m1 * (1 - (1 + u2) ^ -k) / u2 - m2 * (1 + u2) ^ -k
Loop
tauxx = u2
End Function[/B][/COLOR]