No, the opposite of a definition is certainly not always true. That would depend on the definitions and the meaning of the opposite.
Not always
Yes
This is not always true.
Not necessarily. If the statement is "All rectangles are polygons", the converse is "All polygons are rectangles." This converse is not true.
no converse is not true
No.
yes it is
Not always
always true
always true
Yes
No, the converse of a statement does not necessarily have to be true. In this case, the original statement "If you are hungry then you are not happy" does not imply that its converse "If you are not happy then you must be hungry" is always true. It is possible to be unhappy for reasons other than hunger.
No. Consider the statement "If I'm alive, then I'm not dead." That statement is true. The converse is "If I'm not dead, then I'm alive.", which is also true.
This is not always true.
The Answer: NO
No, it must not be true.
Not necessarily. If the statement is "All rectangles are polygons", the converse is "All polygons are rectangles." This converse is not true.