formula to calculate ax plus b power m

let f(x) = \[(ax+b)^m\]

first derivative can be written as  \[\frac{\mathrm{d}{y } }{\mathrm{d} x} \]= \[y_1=ma(ax+b)^{m-1}\]

2nd derivative is given by            \[y_2=m(m-1)a^2(ax+b)^{m-2}\]

3rd derivative can be given as      \[y_3=m(m-1)(m-2)(a^3)(ax+b)^{m-3}\]

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nth derivative is given as       \[y_n=m(m-1)(m-2)..........(m-n+1)(a^n)(ax+b)^{m-n}\]..................(1)

This formula is true for all m

following are the some particular cases 

Case (1)  if m=n (positive)

then  then equation 1 can be simplified as 

\[D^n(ax+b)^n= n(n-1)(n-2).................1*a^n(ax+b)^{n-n}\]

                      =\[n!a^n\]

Case(2) if m is positive integer and m is greater than n

\[D^n(ax+b)^m=  \frac{m(m-1)....(m-n+1)(m-n)(m-n-1) 2 *1}{(m-n)(m-n-1)...2*1}a^n(ax+b)^{m-n}\]

                       =\[ \frac{m!}{(m-n)!}a^n(ax+b)^{m-n}\]

Case 3 when m > 0 and n > m

 \[D^n(ax+b)^m=0\]

case 4 when m=-1 

\[D^n(ax+b)^{-1}=D^n(\frac{1}{ax+b})\]

                         = \[(-1)(-2)(-3).....(-n)(a^n)(ax+b)^{-1-n}\]

                         =\[\frac{(-1)^n n!a^n}{(ax+b)^{n+1}}\]

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