bac-s-maths 2016 Q4 (specialization) Part A

bac-s-maths · France · antilles-guyane Number Theory Linear Diophantine Equations
We consider the following equation with unknowns $x$ and $y$ integers: $$7x - 3y = 1 \tag{E}$$
  1. An incomplete algorithm is given below. Copy it and complete it, writing its missing lines (1) and (2) so that it gives the integer solutions $(x; y)$ of the equation (E) satisfying $-5 \leqslant x \leqslant 10$ and $-5 \leqslant y \leqslant 10$.
    Variables:
    X is an integer
    Y is an integer
    Start:
    For X varying from $-5$ to 10
    (1) \ldots
    (2) \ldots
    Then Display X and Y
    End If
    End For
    End

  2. a. Give a particular solution of equation (E). b. Determine the set of pairs of integers solutions of equation (E). c. Determine the set of pairs $(x; y)$ of integers solutions of equation (E) such that $-5 \leqslant x \leqslant 10$ and $-5 \leqslant y \leqslant 10$.
We consider the following equation with unknowns $x$ and $y$ integers:
$$7x - 3y = 1 \tag{E}$$

\begin{enumerate}
  \item An incomplete algorithm is given below. Copy it and complete it, writing its missing lines (1) and (2) so that it gives the integer solutions $(x; y)$ of the equation (E) satisfying $-5 \leqslant x \leqslant 10$ and $-5 \leqslant y \leqslant 10$.

\begin{center}
\begin{tabular}{|l|}
\hline
Variables: \\
X is an integer \\
Y is an integer \\
Start: \\
For X varying from $-5$ to 10 \\
(1) \ldots \\
(2) \ldots \\
Then Display X and Y \\
End If \\
End For \\
End\\
\hline
\end{tabular}
\end{center}

  \item a. Give a particular solution of equation (E).\\
b. Determine the set of pairs of integers solutions of equation (E).\\
c. Determine the set of pairs $(x; y)$ of integers solutions of equation (E) such that $-5 \leqslant x \leqslant 10$ and $-5 \leqslant y \leqslant 10$.
\end{enumerate}