- Repetitive structure (3 exercices)
- Repetitive structure: study of the stop condition (1 exercice)
- Repetitive structure: studying the threshold of a sequence (4 exercices)
- Repetitive structure: finding the stopping condition (4 exercices)
Valeur deuValeur denu>4500(vrai/faux)57000vraivraifaux
N
←
N+1
End
As
long
as
a
Explain
what
the
value
of
variable
N
represents
at
the
end
of
this
algorithm.
b
Using
the
calculator,
determine
the
value
of
variable
N
at
the
end
of
this
algorithm
and
interpret
the
result.
E.7007
Consider
the
sequence
u
n
is
defined
by
u
0
=5700
and
for
any
natural
number
n
by:
u
n
+1
=1.015
·
u
n
−
300
Consider
the
following
algorithm:
u
←
5
700
n
←
0
As
long
as
u>4500
u
←
1;
015
×
u
−
300
n
←
n+1
End
As
long
as
1
Copy
and
complete
the
table
below,
adding
as
many
columns
as
necessary
between
the
second
and
last
columns.
2
At
the
end
of
the
algorithm’s
execution,
what
is
the
value
of
the
variable
n
?
Interpret
this
value
in
the
context
of
the
exercise.
E.7017
Consider
the
following
algorithm:
U
←
4
N
←
0
As
long
as
U<40
U
←
0;
92
×
U+8
N
←
N+1
End
As
long
as
1
Copy
the
following
table
and
complete
it,
adding
as
many
columns
as
necessary.
The
values
of
U
will
be
rounded
to
the
tenth.
Value
of
U
4
.
.
.
.
.
.
Value
of
N
0
.
.
.
.
.
.
Condition
U
<
40
vraie
.
.
.
.
.
.
2
Give
the
value
of
the
variable
N
at
the
end
of
the
execu-tion
of
this
algorithm.
E.7855
Maya
has
20
e
in
her
piggy
bank
on
June
1
er
2018
.
From
that
date
onwards,
each
month
she
spends
a
quarter
of
the
contents
of
her
piggy
bank
and
then
puts
20
e
more
into
it.
For
any
natural
number
n
,
let
u
n
be
the
amount
of
money
in
Maya’s
piggy
bank
at
the
end
of
the
n
th
month.
We
have
:
u
0
=20
.
We
assume
that
for
any
natural
number
n
:
u
n
+1
=0.75
·
u
n
+20
We
consider
the
following
algorithm:
U
←
20
N
←
0
As
long
as
U<70
U
←
0.75
×
U+20
N
←
N+1
End
While
Display
N
1
Copy
and
complete
the
table
below,
which
outlines
the
different
steps
involved
in
executing
the
algorithm.
Add
as
many
columns
as
necessary
in
place
of
the
dotted
one.
Round
the
results
to
two
decimal
places.
.
.
.
.
.
.
.
.
.
Value
of
U
20
.
.
.
.
.
.
.
.
.
Value
of
N
0
.
.
.
.
.
.
.
.
.
Condition
U
<
70
true
true
false
.
.
.
.
.
.
.
.
.
2
What
value
is
displayed
at
the
end
of
the
execution
of
this
algorithm?
Interpret
this
value
in
the
context
of
the
exercise.
4.
Repetitive
structure:
finding
the
stopping
condition
E.6149
We
consider
the
sequence
u
n
defined
by:
u
0
=
20
;
u
n
+1
=
0.92
·
u
n
+
3
1
On
admits
that
the
general
term
of
the
sequence
u
n
admits
for
expression
:
u
n
=
−
17.5
×
0.92
n
+
37.5
Deduce
the
limit
of
the
sequence
u
n
.
2
a
Recopy
and
complete
the
following
algorithm
so
that
at
the
end
of
its
execution
the
variable
N
represents
the
rank
from
which
the
terms
of
the
sequence
will
have
a
value
greater
than
or
equal
to
25
.
U
←
20
N
←
0
As
long
as
...
U
←
0.92
×
U
+
3
N
←
N
+
1
End
As
long
as
que
b
Using
the
calculator,
determine
the
rank
from
which
the
terms
of
the
sequence
u
n
will
for
the
first
time
be
greater
than
or
equal
to
25
.
https://chingmath.fr
chapExoCorrec/7007
sacados/7007
Valeur deuValeur denu>4500(vrai/faux)57000vraivraifaux
chapExoCorrec/7017
sacados/7017
chapExoCorrec/7855
sacados/7855
Extrait Liban
Mai 2018
chapExoCorrec/6149
sacados/6149
E.6151
1
Determine
by
calculation
the
smallest
value
of
the
natu-ral
number
n
such
that
:
250
+
1250
×
0.8
n
<
500
2
We
consider
the
sequence
u
n
defined
by:
u
0
=
1500
;
u
n
+1
=
0.8
·
u
n
+
50
for
all
n
∈
N
Complete
the
algorithm
below
so
that
at
the
end
of
its
execution,
the
variable
u
has
the
value
obtained
in
the
previous
question
:
u
←
1500
n
←
0
While
......
do
u
←
......
n
←
......
End
While
E.7856
Consider
the
sequence
u
n
de-fined
by
u
0
=65
and
for
any
natural
number
n
:
u
n
+1
=
0.8
·
u
n
+18
We
admit
that
:
u
n
=90
−
25
×
0.8
n
Consider
the
algorithm
below
:
line
1
u
←
65
line
2
n
←
0
que
......
line
4
n
←
n+1
line
5
u
←
0;
8
×
u+18
line
6
Fin
As
long
as
1
Copy
and
complete
the
line
3
of
this
algorithm
so
that
it
determines
the
smallest
natural
number
n
such
that
:
u
n
85
.
2
What
is
the
value
of
the
variable
n
at
the
end
of
the
algorithm’s
execution?
3
Calculate
the
result
of
the
previous
question
by
solving
the
inequation
u
n
85
E.7854
A
company
offers
annual
photo-copier
maintenance
contracts.
The
director
of
this
company
notes
that,
each
year,
14
%
additional
contracts
are
signed
and
7
are
terminated.
In
2017
,
the
company
had
120
contracts.
We
model
the
situation
with
a
sequence
u
n
where
u
n
is
the
number
of
contracts
signed
in
year
2017+
n
.
Thus,
we
have
:
u
0
=120
1
Justify
that,
for
any
natural
number
n
,
we
have
:
u
n
+1
=
1.14
·
u
n
−
7
2
Given
its
current
structural
capacity,
the
company
can
only
take
on
190
contracts.
Beyond
that,
the
company
will
have
to
hire
more
staff.
We
therefore
want
to
know
in
which
year
the
company
will
need
to
hire.
To
do
this,
we
use
the
following
algorithm:
n
←
0
u
←
120
As
long
as
......
n
←
n+1
.........
End
As
long
as
Display
2017+n
a
Copy
and
complete
the
algorithm
above.
b
What
is
the
year
displayed
at
the
end
of
the
algorithm?
Interpret
this
value
in
the
context
of
the
exercise.
https://chingmath.fr
chapExoCorrec/6151
sacados/6151
chapExoCorrec/7856
sacados/7856
chapExoCorrec/7854
sacados/7854