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algebra intermediate
Problem
Find a monic quartic polynomial, in with rational coefficients such that and are roots of the polynomial.
Solution
If is the root of a polynomial with rational coefficients, then so is . Their sum is and their product is Thus, the monic quadratic with roots and is .
If is the root of a polynomial with rational coefficients, then so is . Their sum is and their product is Thus, the monic quadratic with roots and is .
Thus, the monic quartic with roots and is
If is the root of a polynomial with rational coefficients, then so is . Their sum is and their product is Thus, the monic quadratic with roots and is .
Thus, the monic quartic with roots and is
Final answer
x^4-6x^3+8x^2+4x-4