1. **State the problem:** Find the range of values of the constant $k$ for which the line $y = kx$ intersects the curve $y = x^2 + 3kx + 2 - k$ at two distinct points.
2. **Set up the equation for intersection:** At intersection points, the $y$ values are equal, so set the line equal to the curve:
$$kx = x^2 + 3kx + 2 - k$$
3. **Rearrange the equation:** Move all terms to one side:
$$0 = x^2 + 3kx + 2 - k - kx$$
$$0 = x^2 + (3k - k)x + 2 - k$$
$$0 = x^2 + 2kx + 2 - k$$
4. **Analyze the quadratic equation:** The quadratic in $x$ is
$$x^2 + 2kx + (2 - k) = 0$$
For two distinct intersection points, this quadratic must have two distinct real roots.
5. **Use the discriminant condition:** The discriminant $\Delta$ is
$$\Delta = (2k)^2 - 4 \times 1 \times (2 - k) = 4k^2 - 4(2 - k) = 4k^2 - 8 + 4k$$
6. **Simplify the discriminant:**
$$\Delta = 4k^2 + 4k - 8$$
7. **Condition for two distinct real roots:**
$$\Delta > 0$$
$$4k^2 + 4k - 8 > 0$$
8. **Divide both sides by 4:**
$$\cancel{4}k^2 + \cancel{4}k - \cancel{8} > 0$$
$$k^2 + k - 2 > 0$$
9. **Factor the quadratic:**
$$k^2 + k - 2 = (k + 2)(k - 1)$$
10. **Solve inequality:**
$$(k + 2)(k - 1) > 0$$
This product is positive when both factors are positive or both are negative.
- Both positive: $k - 1 > 0 \Rightarrow k > 1$
- Both negative: $k + 2 < 0 \Rightarrow k < -2$
11. **Final answer:**
$$k < -2 \quad \text{or} \quad k > 1$$
Thus, the line $y = kx$ intersects the curve $y = x^2 + 3kx + 2 - k$ at two distinct points if and only if $k < -2$ or $k > 1$.
Line Curve Intersection D0E0F8
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