welcome to this video friends
and today i m going to talk about
an important topic form engineering mathematics
"Leibnitz Theorem"
friends first of all we'll talk about the statement of "Leibnitz Theorem"
so the statement of "Leibnitz Theorem" says
if we have two functions
first function is this and second function is this
ok
and suppose both of these are the functions of 'X"
and both functions are such that
that
we can find find the "nth" derivatives of both functions than
how we'll find the "nth" derivative of product of "u" and "v"
This is all "Leibnitz" about.
when we will find the nth derivative of this
then according to leibnitz theorm it says
we will write it with the help of leibnitz theorem as
now let's prove it
now we will prove this with mathmatical
induction
suppose the product of u and v is y
we have simply applied the chain rule of differentiation here
first we will talk about this part
we get
and this will be
now you see that this part
both are similar
so we add them
And we can write it as if we want
so friends you see that leibnitz is true for
now will solve it further solve it and see
so friends we will differentiate this expression again and see
we get
we get y(m+1)
when we differentiate this
when we differentiate this part we get
we are applying chain rule at this
on differentiating this part we get
we keep it as it is
when we differentiate this it becomes
we left v1 here
in the next step we will differentiate v1 and keep these terms as it is
now we will talk about this term
and we will apply chain rule here
mc2 is a constant part so it will remain as it is
in the next part we shall leave Um+2
and will differentiate V2
and it will further go like this
so friends you are noticing here
that there are some pairs forming
similarly from next two terms we get
so taking parts which are common into these terms
and these are our common terms so
we get here
similarly we get here
is
so we can write these expressions as