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Integration question-can anyone help?

4x7

5

how would you integrate this? I know that you need to simplify first but I don't know what to do in this sort of situation.
Original post by Mathsgu
4x7

5

how would you integrate this? I know that you need to simplify first but I don't know what to do in this sort of situation.


Is there anything missing from the question?

That is fine as it is and you can integrate it. Remember that integration is the opposite of differentiation. If you differentiate a*x^n you get a*nx^(n-1). So the opposite, integration, would be raising the power by 1 and then dividing by the new power.
Reply 2
Hi :smile:

First of I believe you should revise, or watch some videos on youtube. Take this one https://www.youtube.com/watch?v=r-Mu9N_BEJs for example. Your question is rather simple, so try to do it yourself so you can get better.

But if you need worked solutions, I can do it for you!
Reply 3
Original post by SeanFM
Is there anything missing from the question?

That is fine as it is and you can integrate it. Remember that integration is the opposite of differentiation. If you differentiate a*x^n you get a*nx^(n-1). So the opposite, integration, would be raising the power by 1 and then dividing by the new power.


Yes it is only one part of the question but this was the part I was struggling with. I know that you have to raise the power then divide by the new power but I wasn't sure how. I was thinking that you would have to simplify it first but I don't know where to begin.

If you have any pointers on how to simplify something like this that would be useful :smile:
Original post by Mathsgu
Yes it is only one part of the question but this was the part I was struggling with. I know that you have to raise the power then divide by the new power but I wasn't sure how. I was thinking that you would have to simplify it first but I don't know where to begin.

If you have any pointers on how to simplify something like this that would be useful :smile:


Well, when integrating you can take constants out of the integral, so if you're looking for ∫4x7 dx\int 4x^7\ dx you can take the constant out of the integral, so you're left with 4∗∫x7 dx 4 * \int x^7\ dx, which means you just need to find the integral of x^7 and multiply it by 4.
Reply 5
Original post by SeanFM
Well, when integrating you can take constants out of the integral, so if you're looking for ∫4x7 dx\int 4x^7\ dx you can take the constant out of the integral, so you're left with 4∗∫x7 dx 4 * \int x^7\ dx, which means you just need to find the integral of x^7 and multiply it by 4.


Ok that makes sense :smile: I was starting to divide with fractions and it was coming out with a very nice number! Thanks
Reply 6
Original post by SeanFM
Well, when integrating you can take constants out of the integral, so if you're looking for ∫4x7 dx\int 4x^7\ dx you can take the constant out of the integral, so you're left with 4∗∫x7 dx 4 * \int x^7\ dx, which means you just need to find the integral of x^7 and multiply it by 4.


What would you do with the /5 part of the question? Would you integrate that separately?
(edited 8 years ago)
Original post by Mathsgu
What would you do with the /5 part of the question? Would you integrate that separately?


I was wondering what that 5 was! :colondollar:

If it's integral of (4/5) * x^7 then you can just take it out as it is a constant, so it becomes (4/5) * integral of x^7.
Reply 8
Original post by SeanFM
I was wondering what that 5 was! :colondollar:

If it's integral of (4/5) * x^7 then you can just take it out as it is a constant, so it becomes (4/5) * integral of x^7.


Oh ok xD probably me not writing it down very clearly!! Thanks again

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