Can you help me figure out what sort of answer my professor is looking for (differential equations)?

Asked by Mariah (25883

) January 19th, 2012

We have web-based homework assignments and this question is baffling me. I know how to solve that equation, but the method I would use doesn’t involve rewriting it in the form that they’re prompting; I’ve never seen that form before and don’t know what it is. He hasn’t taught us anything like that, and I can’t find anything like it in the textbook. Any ideas?

I do not want help whatsoever on actually solving the problem.

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5 Answers

Does this help?

http://www2.math.umd.edu/~jmr/241/doubleint.html

bkcunningham (18501

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Thank you, @bkcunningham. It’s not a double integral, though.

Mariah (25883

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I think the first part is c as in a constant y(x) = c + integral….

I haven’t thought about this in almost 30 years.

Like, what is the integral of d(cabin)/cabin? The answer is log cabin + c

Charles (4826

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@Charles is correct, this is an initial value problem. Let I be the integral of y’ from 0 to t. By the Fundamental Theorem of Calculus, I = y(t) – y(0); that is y(t) = y(0) + I.

ratboy (15172

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Thanks folks. Actually I ended up getting help from my TA, who told me pretty much the same thing as @ratboy. I have no problem with IVPs but the form of this one just threw me off. I (stupidly) didn’t catch the fact that the two stacked spaces labelled “t =” were to be the limits of integration. Duh! Once I caught that it was no problem. Thanks again.

Mariah (25883

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