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- General Solution of $y' = x \, \ln x$
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- Special products and factoring
- Newton's Law of Cooling
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- Eliminate the Arbitrary Constants
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## Recent comments

- 400000=120[14π(D2−10000)]

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## With the headwind or flying

With the headwind or flying against the wind, the net speed of flying is $v_\text{airplane} - v_\text{wind}$. And with the tailwind or flying with the wind, the net speed is $v_\text{airplane} + v_\text{wind}$. From $s = vt$, we will use $t = \dfrac{s}{v}$ to define the total time of 5 hours.

$t_\text{headwind} + t_\text{tailwind} = 5$

$\dfrac{d}{300 - 30} + \dfrac{d}{300 + 30} = 5$

$\dfrac{2d}{927} = 5$

$d = 742.5 \text{ miles}$