Let's analyze the functions \( f(x) = 2\sqrt{x} \) and \( g(x) = 2\sqrt[3]{x} \) to determine which of the given statements is true.
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Both graphs go through (-1,-1), (0,0), and (1,1):
- \( f(-1) \) is not defined since square root of a negative number is not a real number. Thus, this statement is false.
- \( f(0) = 2\sqrt{0} = 0 \) and \( g(0) = 2\sqrt[3]{0} = 0 \), so they both go through (0,0).
- \( f(1) = 2\sqrt{1} = 2 \) and \( g(1) = 2\sqrt[3]{1} = 2 \), so they both go through (1,1).
Therefore, this statement is false since both functions do not go through (-1,-1).
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When \( x > 1 \), the function \( g(x) = 2\sqrt[3]{x} \) is greater than \( f(x) = 2\sqrt{x} \):
- For \( x > 1 \), let's evaluate \( f(2) \) and \( g(2) \):
- \( f(2) = 2\sqrt{2} \approx 2.828 \)
- \( g(2) = 2\sqrt[3]{2} \approx 1.587 \)
Since \( 2\sqrt{2} > 2\sqrt[3]{2} \), this statement is false.
- For \( x > 1 \), let's evaluate \( f(2) \) and \( g(2) \):
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The graphs have different domains:
- The domain of \( f(x) = 2\sqrt{x} \) is \( x \geq 0 \) (only non-negative values).
- The domain of \( g(x) = 2\sqrt[3]{x} \) is all real numbers (no restrictions).
Therefore, this statement is true.
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They are both decreasing on their domains:
- \( f(x) = 2\sqrt{x} \) is increasing on \( x \geq 0 \).
- \( g(x) = 2\sqrt[3]{x} \) is also increasing on all real numbers.
Therefore, this statement is false.
Conclusion:
The only true statement is: The graphs have different domains.