Question

i need help please


If a and b are odd integers, then a • b is an odd integer.

Which is the inverse of the statement?


If a and b are not odd integers, then a • b is not an odd integer.
If a • b is an odd integer, then a and b are odd integers.
a and b are odd integers
a • b is an odd integer

Answer 1

hint:
if a and b are odd integers, then exists two integers, say m, and n, such that:
\[\begin{gathered}
a = 2n + 1 \hfill \\
b = 2m + 1 \hfill \\
\end{gathered} \]

Answer 2

so we can write:
\[a \cdot b = 4nm + 2n + 2m + 1\]