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# Integration with term outside brackets watch

1. I thought that I would isolate the z coeffecient and brackets, to give me, z^2, 5z^2/2

However, according to an online integral calcuator, the correct answer is 2z^3+15z^2/6

Im sorry; but, the latex wont let me put down 20 and 10 for the integration, that is what the original question is asking.

Where am I going wrong?
2. (Original post by apronedsamurai)

I thought that I would isolate the z coeffecient and brackets, to give me, z^2, 5z^2/2

However, according to an online integral calcuator, the correct answer is 2x^3+15x^2/6

Im sorry; but, the latex wont let me put down 20 and 10 for the integration, that is what the original question is asking.

Where am I going wrong?
Are you integrating wrt to z

Why is the x there
3. Sorry that was a typo. What is wrt?
4. (Original post by apronedsamurai)
Sorry that was a typo. What is wrt?
If we get rid of the x are we integrating dz

Look at the corrected version I have posted in post 2 is that what you are integrating

If so multiply the bracket out and integrate as normal
5. Sorry, again, the all the x's were mistakes. Z's
6. (Original post by apronedsamurai)
Sorry, again, the all the x's were mistakes. Z's
Again

Please look at what I have put in post 2 is that what you want to integrate
7. Yes, it is.
8. (Original post by apronedsamurai)
Yes, it is.
Then

As I said

Multiply out the bracket and integrate as normal

You can not just integrate the separate bits
9. Multiplying out the brackets (before integration) yields me z^2+5z?
10. Would I need to use the substitution method here?
11. (Original post by apronedsamurai)
Multiplying out the brackets (before integration) yields me z^2+5z?

(Original post by apronedsamurai)
Would I need to use the substitution method here?
Why do you think you need to substitute

Increase the power and divide

Btw if you use the reply button on my post I will get a notification that you have replied to me
12. That is what I am confused by. Do i raise the power of the Z coeffiecent (the Z term outside the brackets) or do I multiply out the brackets, THEN raise the power by one?
13. (Original post by apronedsamurai)
That is what I am confused by. Do i raise the power of the Z coeffiecent (the Z term outside the brackets) or do I multiply out the brackets, THEN raise the power by one?

You cannot apply integration rules to the separate parts

You have multiplied the bracket - NOW you integrate
14. Thank you very much.

I got the correct answer (3083 and a third)

I was thrown by the online calculator, as it had gave such a wildly different result, with regards to the integration of the terms :| Perhaps that was just an input error, or I interperted the information incorrectly.

Regardless, I have now taken another step towards understanding integration. Thank you.
15. (Original post by apronedsamurai)

I thought that I would isolate the z coeffecient and brackets, to give me, z^2, 5z^2/2

However, according to an online integral calcuator, the correct answer is 2z^3+15z^2/6

Im sorry; but, the latex wont let me put down 20 and 10 for the integration, that is what the original question is asking.

Where am I going wrong?
The online calculator is wrong, the answer should be (x^3)/3+(5x^2)/2 . I'm not sure how you got to that answer.
16. I got that answer because I am a moron
17. (Original post by apronedsamurai)
Thank you very much.

I got the correct answer (3083 and a third)

I was thrown by the online calculator, as it had gave such a wildly different result, with regards to the integration of the terms :| Perhaps that was just an input error, or I interperted the information incorrectly.

Regardless, I have now taken another step towards understanding integration. Thank you.
No problem

The online calculator gave you the correct result for the integration ... But you can do it now anyway 😀
18. (Original post by apronedsamurai)
I got that answer because I am a moron
lol no you're not! anyways are you doing A levels or something similar at a school? Or are you studying calculus on your own?
19. (Original post by gagafacea1)
The online calculator is wrong, the answer should be (x^3)/3+(5x^2)/2 . I'm not sure how you got to that answer.
The online calculator gave that ... It simply added the fractions
20. (Original post by TenOfThem)
The online calculator gave that ... It simply added the fractions
oh yeah sorry, I interpreted that as (2z^3)+(15z^2/6)

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