f(x) is a quadratic expression such that the coefficient of x2 is positive. If the roots of f(x) = 0 lie on either sides of x = -1, then which of the following is necessarily true about f(-1)?
Explanation:
Since the coefficient of x2 is positive, the graph of the quadratic function will be upward facing such that its roots lie on either sides of x = -1.
The graph would look something like this.
From the graph it is clear that f(-1) is less than zero.
Hence, option (b).
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