1. f(x) < 0
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f(x) > 0
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If x < 0, then f(x) < 0
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If x > 0, then f(x) > 0
The answer is 4 but i don’t know why. So if you gyzz could give me a good explanation it would really help. Thank you 😀
1 Answer
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The first 2 you can dismiss completely because you can’t prove either one of those for all x (if x = -30, for instance, 1/3 * (-30) + 9 = -10 + 9 = -1). In fact, let’s assume x = -3. Then 1/3 * (-3) + 9 = -1 + 9 = 8. That alone also disproves C). D) is true for all x > 0, because if x = 0, you’d get 9, the minimum value under the subset.
