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# Substitution Tweet

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1. Substitution
can some one please solve the question.
Integrate xsqrt(2^x+1) dx using U=2x^2+1

2. Re: Substitution
3. Re: Substitution
(Original post by bahjat93)
can some one please solve the question.
Integrate xsqrt(2^x+1) dx using U=2x^2+1

See file
Attached Files
4. Integration Problem.pdf (42.1 KB, 26 views)
5. Re: Substitution
Since the solution has been given, I will simply say

I find it really annoying that A Level exam boards push for the use of substitution in questions that can be solved by simple inspection
6. Re: Substitution
(Original post by bahjat93)
can some one please solve the question.
Integrate xsqrt(2^x+1) dx using U=2x^2+1

I think there is an error in the question.
7. Re: Substitution
(Original post by steve2005)
I think there is an error in the question.
but an obvious one
8. Re: Substitution
(Original post by steve2005)
I think there is an error in the question.

(Original post by TenOfThem)
Since the solution has been given, I will simply say

I find it really annoying that A Level exam boards push for the use of substitution in questions that can be solved by simple inspection

(Original post by mikelbird)
See file
The questions was wrong apparently, i mailed my teacher and he said to skip that question -_-.
Can you please tell me how to do this question.
Integrate xsqrt((x^2)+5) by using u=x^2+5
(You have to do it by substitution and can you please show it to me as well )

I don't know how to get rid of one of the x after you differentiate
9. Re: Substitution
(Original post by bahjat93)
The questions was wrong apparently, i mailed my teacher and he said to skip that question -_-.
Can you please tell me how to do this question.
Integrate xsqrt((x^2)+5) by using u=x^2+5
(You have to do it by substitution and can you please show it to me as well )

I don't know how to get rid of one of the x after you differentiate
Substitute it in to get:
Integrate xsqrt(u)
Find du/dx and that should give you a clue. Remember you're trying to find it in terms of du rather than dx after substitution
10. Re: Substitution
(Original post by Mikeyyy!)
Substitute it in to get:
Integrate xsqrt(u)
Find du/dx and that should give you a clue. Remember you're trying to find it in terms of du rather than dx after substitution
steveyy dude gave me the answer so it's all good