Answer:
f(x) = x^2 - 3x + 1.
Step-by-step explanation:
If the roots of this polynomial are 1 and 2, the corresponding factors are (x - 1) and (x - 2). Multiplying, we get
f(x) = (x - 1)(x - 2) = x^2 - 3x + 1
The polynomial of least degree with roots 1 and 2 is f(x) = x^2 - 3x + 1.
