If you want to have an infinitestimally small change, you end up writing dh is dq sub p.

这是对于有限的变化而言的,如果是一个无限小的变化。

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You make the volume infinitely large, the density of the gas infinitely small.

密度无限小，气体分子之间的相互作用。

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as long as it's small and finite, will lead to some small infinite errors in the formula, but remember it's got to be in the end made to be vanishingly small.

只要它只是有限小,就会在公式中引起无限小的误差,但请记住,Δt最后变得难以察觉地小

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