Definition of whethe:
°Used to introduce an interrogative content clause (indirect question) that consists of multiple alternative possibilities, and indicate uncertainty between them;
if.
"He chose the correct answer, but whether by luck or by skill I don't know."
°Used to introduce a yes-or-no interrogative content clause (indirect question) that consists of a single possibility, and indicate uncertainty over it;
if, whether or not.
"Do you know whether he's coming?"
Definition of whethe:
°Used to introduce an interrogative content clause (indirect question) that consists of multiple alternative possibilities, and indicate uncertainty between them;
if.
"He chose the correct answer, but whether by luck or by skill I don't know."
°Used to introduce a yes-or-no interrogative content clause (indirect question) that consists of a single possibility, and indicate uncertainty over it;
if, whether or not.
"Do you know whether he's coming?"