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Let $b$ be a constant. What is the smallest possible degree of the polynomial f(x) + b*g(x)?
Let f(x) = x^4-3x^2 + 2 and g(x) = 2x^4 - 6x^2 + 2x -1.
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Regularly, we expect that f(x) + b*g(x) is the 4-degree polynomial. But if you take b= -1/2,
the terms containing x^4 will cancel each other; the terms containing x^2 also will cancel each other,
and then you will get the sum f(x) + b*g(x) as the polynomial of the degree 1 (one),
which is a linear binomial. So, the smallest possible degree is 1 at b = -1/2.
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