Showing posts with label Sequence and Series; Engineering Mathematics. Show all posts
Showing posts with label Sequence and Series; Engineering Mathematics. Show all posts

Chapter 4: Successive Differentiation

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Successive Differentiation

Let  be a function of  the derivative or

Differential coefficient of  w.r.t.  is denoted by

Where  

Similarly the second order derivative of y w.r.t. x is defined as

Similarly we get nth derivative or

Differential coefficient of  w.r.t.  and is denoted by

 

Application:

1.    Series expansion of a function like Taylor’s and McLaurin's series expansion.

2. Solution of ordinary and partial differential equations.

Ex. Using Taylor’s Series

Example 1: Find the nth derivative of

Solution: differentiating y w.r.t. x we get,

          …….......(1)

Differentiating again w.r.t. x, we get

…….......(2)

Similarly differentiating successively, we get

             …….......(3)

.......(4)

          

    .......(5)

Example 2: Find the nth derivative of

Solution: differentiating y w.r.t. x we get,

          …….......(1)

Differentiating again w.r.t. x, we get

        …….......(2)

Similarly differentiating successively, we get

      …….......(3)

                    .......(4)

          

.......(5)

Example 3: Find the nth derivative of

Solution: differentiating y w.r.t. x we get,

            …….......(1)

Differentiating again w.r.t. x, we get

....(2)

Similarly differentiating successively, we get

…….......(3)

      ….........(4)

          

            .......(5)

Example 4: Find the nth derivative of

Solution: differentiating  w.r.t.  we get,

                         

        …….......(1)

Differentiating again w.r.t. , we get

…….......(2)

Similarly differentiating successively, we get

…….......(3)

Successively differentiating  w.r.t.   ,we get

…….......(4)

… … … … … … … …

The nth order derivative of y is given as



Example 5: Find the nth derivative of

Solution: differentiating  w.r.t.  we get,

                         

        …….......(1)

Differentiating again w.r.t. , we get

…….......(2)

Similarly differentiating successively, we get

…….......(3)

Successively differentiating  w.r.t.   ,we get

                            …….......(4)

… … … … … … … …

The nth order derivative of y is given as



Text Box: 〖  y〗_n=a^n.cos(ax+b+n.Ï€/2)
 Example 6: Find the nth derivative of

Solution: differentiating  w.r.t. we get,

      

 .......(1)

Here we consider  

Thus we have   and

Now substituting these values in (1) we get,



Text Box: Formula: sin(A+B)=sinAcosB+cosAsinB
 

 


differentiating   again w.r.t. we get,

      

    .......(2)

Again, we consider  

Thus we have   and

Now substituting these values in (2) we get,

Thus we have

 

… … … … … … … … … … …

Example 7: Find the nth derivative of

Solution: differentiating  w.r.t.  successively, we get

                       

… … … … … … … … … … …

Case- I

Case- II                      

Case- III 

Case- IV

Case- V

 

Example 8: Find the nth derivative of

Solution: differentiating  w.r.t.  we get,

                       

Differentiating again  times w.r.t. , we get



Text Box: d(1/((ax+b) ))/dx=(a^n.(-1)^n.n!)/(ax+b)^(n+1)
 

 

 


Example 9: Find the nth derivative of

Solution: we have

Let

Putting   we get

 

Putting   we get

Thus 

Differentiating w.r.t. x n times we get,

For

Compare with the formula

If  then

Here , hence

Differentiating w.r.t. x n times we get,

For   

Compare with the formula

If  then

Here , hence

Differentiating w.r.t. x n times we get,

 


Assignment: Probability and Statistics Basic

Sticky Ad Probability Problems with Detailed Solutions Click each question to expand the detailed interpretation and solution. ...