End behavior

What this lesson shows

y = x² − 4. Forget the middle for a moment. What happens at the far EDGES — when x gets huge, or hugely negative?

Try it yourself

Real questions from this lesson's worksheets — answers below each one.

1. As x → −∞, the end behavior of f(x) = -x⁵ + 2x - 1 is f(x) → ?
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   +∞
2. As x → −∞, the end behavior of f(x) = -3x² + 2x - 1 is f(x) → ?
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   −∞
3. As x → −∞, the end behavior of f(x) = x² + 2x - 1 is f(x) → ?
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   +∞
4. As x → −∞, the end behavior of f(x) = 3x⁴ + 2x - 1 is f(x) → ?
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   +∞