Question:If are distinct numbers, find a polynomial of degree which is at and 0 at for . Hint: the product of all for is zero at if . .

Confusion:The part of the question that I don't understand is the 'which is at and 0 at for .' What are and ? Does it mean that for any two numbers we choose from the sequence , we get as 0, for one, and 1, for the other? And how would you go about finding this polynomial?