f(X) = e(X) + o(X)
f(-X) = e(X) - o(X)
From there you can explicitly solve the system of linear equations to get e(X) and o(X)
f(X) = e(X) + o(X)
f(-X) = e(X) - o(X)
From there you can explicitly solve the system of linear equations to get e(X) and o(X)