The Student Room Group

Differentiation of Exponential Functions - Question

How do I go about differentiating xex^2 ?

I started by letting u = x and v = ex^2 , so du/dx = 1 but I don't know how to find dv/dx.

Any help would be greatly appreciated!

Thanks!
Original post by grace15
How do I go about differentiating xex^2 ?

I started by letting u = x and v = ex^2 , so du/dx = 1 but I don't know how to find dv/dx.

Any help would be greatly appreciated!

Thanks!


Use the chain rule on ex2e^{x^2}

Let w=x2w=x^2
(edited 6 years ago)
Reply 2
Original post by ghostwalker
Use the chain rule on
Unparseable latex formula:

e^x^2



So if I let y= (ex )2 then dy/dx = 2 (ex )(ex ) = 2ex^2 ?
So, you have to do x' * (e^(x^2)) + x*((e^(x^2))'
Its the formula u'v + uv'
Original post by grace15
So if I let y= (ex )2 then dy/dx = 2 (ex )(ex ) = 2ex^2 ?


I edited my previous post to suggest the substitution.


NOTE: ex2(ex)2e^{x^2}\not=(e^x)^2

Edit:

(ex)2=ex×ex=e2x(e^x)^2 =e^x\times e^x = e^{2x}
(edited 6 years ago)
Reply 5
So if I let v=ew and let w = x2 then dy/dx of ex^2 is 2xex^2 ?

Then would I use the product rule to get dy/dx = x(2xex^2 ) + ex^2 ?

Which would simplify to ex^2 (2x2 + 1) ?

Is this correct?
Yes.
Original post by grace15
So if I let v=ew and let w = x2 then dy/dx of ex^2 is 2xex^2 ?


Yes.


Then would I use the product rule to get dy/dx = x(2xex^2 ) + ex^2 ?

Which would simplify to ex^2 (2x2 + 1) ?

Is this correct?


And yes.
Reply 8
Original post by ghostwalker
Yes.



And yes.


Great! Thank you very much for your help! :smile:

Quick Reply

Latest