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MarcAReed

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**Calculus Integration from -10 to 0 Yields a Strange Result [RESOLVED]**

As part of a far greater enquiry, I found myself integrating:

[itex]\int^{0}_{-10}x^3+2dx[/itex]

So, I began integrating the [itex]x^3+2[/itex] component, yielding the result of:

[itex][\frac{x^4}{4}+2x]^{0}_{-10}[/itex]

Which can then be set out as a subtraction, by:

[itex][\frac{0^4}{4}+2(0)]-[\frac{-10^4}{4}+2(-10)][/itex]

The left term of the subtraction results in zero, whereas the right results in -2520, thus yielding the overall answer of:

[itex]0--2520=0+2520=2520[/itex]

However, a most curious thing occurs, when I integrate the same definite integral on my calculator -- I get a different answer:

[itex]-2480[/itex]

Not only can an area not be negative, but it defies my previous answer. So, now I have been lead to no other choice, but to ask you all for help, as to seeing where I went wrong.

Thankyou in advance, mes amis.

NOTE: I have a strong feeling that the mistake lies in either my own fault, or in my own lack of knowledge.

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