Bonjour,
Ex2)
1a)
Un+1 = Un+r
Un+1 = Un-250
1b)
U1 = 5000-250 = 4750
U2 = 4750-250 = 4500
U3 = 4500-250 = 4250
2a)
Un = Uo+nr
Un = 5000-250n
2b)
U20 = 5000-20*250
U20 = 5000-5000
U20 = 0
3)
Si Un = 1/2 Uo Un = 5000/2 = 2500
Un = 5000-250n = 2500
250n = 5000-2500 = 2500
n = 2500/250
n = 10
Ex3)
1a)
Cn+1 = q*Cn --> q = 1.0225
1b)
Co = 1000
C1 = 1022.5
C2 = 1045.50625
C3 = 1069.030140625
2)
[tex]C_n=C_o*q^n[/tex]
3)
C31 = 1993.25479293274
C32 = 2038.10302577373
Si [tex]C_n\geq2C_0[/tex]
[tex]C_n\geq2000[/tex]
[tex]C_3_1<2000[/tex]
[tex]C_3_2>2000[/tex]
--> n = 32
J'espère que tu as compris
a+
