1. **Problem statement:** Given the family of functions defined for $k > 0$ by
$$f_k(x) = \frac{1}{2k} \cdot x^2 \cdot (x - 2k)^2,$$
show that for each $k$ there are exactly two zeros and find them.
2. **Finding zeros:** To find zeros, solve $f_k(x) = 0$:
$$\frac{1}{2k} \cdot x^2 \cdot (x - 2k)^2 = 0.$$
Since $\frac{1}{2k} \neq 0$ for $k > 0$, zeros occur when either
$$x^2 = 0 \quad \text{or} \quad (x - 2k)^2 = 0.$$
This gives
$$x = 0 \quad \text{or} \quad x = 2k.$$
3. **Number of zeros:** Both zeros are distinct for $k > 0$ because $0 \neq 2k$. Each zero has multiplicity 2 (due to the squares), so the graph touches the x-axis at these points but does not cross it.
4. **Conclusion:** For each $k > 0$, $f_k$ has exactly two zeros at
$$x = 0 \quad \text{and} \quad x = 2k.$$
Zeros F_K 5907Cf
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