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The function f(x) = (x-2)²(x+3) has a zero at x=2. What is the behavior of the graph of f at this zero?

The function f(x)=(x−2)2(x+3)f(x) = (x-2)^2(x+3) has a zero at x=2x=2. What is the behavior of the graph of ff at this zero?

Answer and explanation

Answer: B: The graph touches the x-axis at x=2 but does not cross it.

The factor (x−2)2(x-2)^2 has even multiplicity, 2, at the zero x=2x = 2. When a zero has even multiplicity, the graph touches the xx-axis and turns around, like the vertex of a parabola, without crossing. That is choice B. The other factor (x+3)(x+3) has multiplicity 1, so the graph crosses at x=−3x = -3. Choice A would be correct only for an odd multiplicity of 1. Choice C is wrong because a vertical asymptote needs a factor in the denominator. Choice D is wrong because f(2)=0f(2) = 0 is perfectly defined, since the function is a polynomial.

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