Differentiate F(x)=(25+v)/v

Whenever there is an equation in the form f(x)=u/w, the quotient rule tells us that:

   f '(x)= [w(du/dx)-u(dw/dx)]/v2  *It looks complecated but if you break it down, it is simple.

All you need is u, v, du/dx and dv/dx, which in this case is:

        u=25+v        w=v2

 du/dx=1        dw/dx=2v      <- All I did was differentiate polynomials differentiation

Sub these into our equation part by part:

w(du/dx)=1*v2=v2    u(dw/dx)=(25+v)*2v=50v+2v2 => -u(dw/dx)=-50v-2v2   w2=(v2)2=v4

Now sub in:

f '(x)=(v2-50v-2v2)/v4=(-50v-v2)/v4

Now cancel a v as it occurs in all parts of the equation:

f '(x)=(-50-v)/v3=-(50+v)/v3

And there is our answer, nothing more can be done to it.

NS
Answered by Nathaniel S. Maths tutor

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