Second derivative

[Idontunderstand]

So I am a little confused with this.


Why is this not the second derivative


Also should the one 2t be negative as well as the 2 in the last part? It has been a while since I have done a derivative.

I see the first derivative as UV+WXZ where each letter is a function, this is should do U`V+V`U+W`XZ+X`WZ+Z`WX or did I completely forget the rules?

 

[Deleted member 4993]

So I am a little confused with this.
View attachment 3117

Why is this not the second derivative
View attachment 3118
Also should the one 2t be negative as well as the 2 in the last part?

Yes. However, those two (-ve) signs after multiplication becomes (+ve).

It has been a while since I have done a derivative.

I see the first derivative as UV+WXZ where each letter is a function, this is should do

(UV+WXZ)' = (UV)' + (WXZ)' = U`V+V`U+W`XZ+X`WZ+Z`WX ....... This is correct

or did I completely forget the rules?

My calculation for M" is same as the first one.

I cannot tell where you made the mistake - because I cannot see your work