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Integration help urgent C4

Can someone explain to me why the integral of 1/root(1+2x) = root(1+2x)

thanks
Reply 1
Original post by mcfc2009
Can someone explain to me why the integral of 1/root(1+2x) = root(1+2x)

thanks


11+2x dx=(1+2x)12 dx \displaystyle \int \frac1{\sqrt{1+2x}} \ dx = \int (1+2x)^{ - \frac12} \ dx

Now its simple integration.
Reply 2
What do you get when you differentiate (1+2x)12(1+2x)^{\frac{1}{2}}
Reply 3
2(1+2x)^1/2
Reply 4
Original post by TenOfThem
What do you get when you differentiate (1+2x)12(1+2x)^{\frac{1}{2}}


I get 2(1+2x)^1/2
Reply 5
Original post by mcfc2009
I get 2(1+2x)^1/2


Why haven't you multiplied by and decreased the power
Reply 6
Original post by TenOfThem
Why haven't you multiplied by and decreased the power


Ive brought it up to the top and made it (1+2x)^-1/2 increase the power by 1 to 1/2 then divided by a half which then gave me 2(1+2x)^1/2
Reply 7
Original post by mcfc2009
Ive brought it up to the top and made it (1+2x)^-1/2 increase the power by 1 to 1/2 then divided by a half which then gave me 2(1+2x)^1/2


Sorry

You have lost me

I thought you were answering the question that I asked and you quoted
Reply 8
+c

I hate integration so much.
Reply 9
Original post by mcfc2009
Ive brought it up to the top and made it (1+2x)^-1/2 increase the power by 1 to 1/2 then divided by a half which then gave me 2(1+2x)^1/2


(ax+b)d dx=1d+1(ax+b)d+1×1a+C \displaystyle \int (ax+b)^{ d } \ dx = \frac1{d+1} (ax+b)^{d+1} \times \frac1{a} +C
Reply 10
Original post by TenOfThem
Sorry

You have lost me

I thought you were answering the question that I asked and you quoted


it started as 1/(1+2x)^1/2 then I followed the method i stated above.
Original post by mcfc2009
it started as 1/(1+2x)^1/2 then I followed the method i stated above.


Yes, I realise that ... but, as you know you got it wrong ...

I was asking you what you get when you differentiate (1+2x)12(1+2x)^{\frac{1}{2}}

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