27.12.2013 Views

Syllabus Vector Differentiation - Velocity and Acceleration - Gradient ...

Syllabus Vector Differentiation - Velocity and Acceleration - Gradient ...

Syllabus Vector Differentiation - Velocity and Acceleration - Gradient ...

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

Engineering Mathematics - II - <strong>Vector</strong> Calculus - 2007<br />

If f1, f2 <strong>and</strong> f3 are differentiable then we define<br />

<br />

d f f(t t) f(t)<br />

df <br />

1 df <br />

2 df <br />

lim i j <br />

3<br />

k<br />

dt t0<br />

t dt dt dt<br />

Similarly higher order derivatives can also be defined.<br />

Note:<br />

<br />

d f <br />

0<br />

dt<br />

iff<br />

<br />

f<br />

is<br />

a<br />

cons tan t<br />

vector .<br />

Rules of differentiation<br />

1. If<br />

g(t) is<br />

a<br />

scalar<br />

function<br />

of<br />

t<br />

<strong>and</strong><br />

<br />

f (t) is a<br />

vector<br />

function<br />

of<br />

<br />

d d f d <br />

scalar t then ( f) f<br />

dt dt dt<br />

2. If<br />

<br />

<strong>and</strong><br />

<br />

are<br />

scalar<br />

cons tan ts,<br />

<br />

f<br />

<strong>and</strong><br />

<br />

g<br />

are vector<br />

functions of<br />

t<br />

then<br />

d<br />

dt<br />

<br />

( f<br />

<br />

<br />

g)<br />

<br />

<br />

d f<br />

<br />

dt<br />

<br />

<br />

d g<br />

<br />

dt<br />

3.<br />

d<br />

dt<br />

Proof:<br />

<br />

( f . g)<br />

<br />

d g<br />

f .<br />

dt<br />

<br />

d f <br />

. g<br />

dt<br />

<br />

Let f f1<br />

i f2<br />

j f3<br />

k<br />

<br />

f . g<br />

<br />

g g1<br />

i g2<br />

j g3<br />

k<br />

f1 g1<br />

f2<br />

g2<br />

f3<br />

g3<br />

d dg1<br />

df1<br />

dg2<br />

df2<br />

dg3<br />

df3<br />

( f . g) f1 g1<br />

f2<br />

g2<br />

f3<br />

g3<br />

dt<br />

dt dt dt dt dt dt<br />

dg<br />

<br />

<br />

<br />

1 dg<br />

<br />

2 dg<br />

<br />

3 df<br />

<br />

1 df<br />

<br />

2 df<br />

f<br />

<br />

3<br />

1 f2<br />

f3<br />

g1<br />

g2<br />

g3<br />

<br />

dt dt dt dt dt dt <br />

<br />

d g<br />

f .<br />

dt<br />

<br />

df <br />

. g<br />

dt<br />

Page 23 of 72

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!