Leibnitz theorem

[willow trench]

If you help, could you show your working out pls.

[waxen stone]

let u = e^x + 1

v = 1/e^x - 1

then d^3y/dx^3 = u''' + 3u''v' + 3u'v'' + v'''

i think

[willow trench]

could you attempt it and send me your workings out pls

[potent path]

Try it using the substitution he gave

He isn’t going to do the work for you I’m afraid

[willow trench]

I did

[potent path]

Send your workings

[waxen stone]

correct, written solutions require a £10 one off fee

[next birch]

@willow trench do you still need help

[potent path]

That’s more like it

[willow trench]

finally solved