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Thomas Calculus 13th [Solutions]

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1172 Chapter 16 Integrals and Vector Fields<br />

Clear[x, y, z, t, f, r, v]<br />

f[x_,y_, z_]: [y<br />

[a, b] {0,2 };<br />

x[t_]: 2 Cos[t]<br />

y[t_]: 3 Sin[t]<br />

z[t_]: 1<br />

r[t_]: {x[t], y[t],z[t]}<br />

v[t_]: r [t]<br />

integrand<br />

2<br />

y z Cos[x, y, z], x +x z Cos[x, y, z], z+ x y Cos[x y z]}<br />

f[x[t], y[t],z[t]] v[t]/Simplify<br />

NIntegrate[integrand (t, a, b}]<br />

16.3 PATH INDEPENDENCE, POTENTIAL FUNCTIONS, AND CONSERVATIVE FIELDS<br />

P N M P N M<br />

y z z x x y<br />

1. x , y , z Conservative<br />

P N M P N M<br />

y z z x x y<br />

2. x cos z , y cos z , sin z Conservative<br />

P<br />

y<br />

3. 1 1<br />

N<br />

z<br />

N<br />

x<br />

Not Conservative 4. 1 1 Not Conservative<br />

M<br />

y<br />

N<br />

x<br />

5. 0 1<br />

M<br />

y<br />

Not Conservative<br />

P N M P N x M<br />

y z z x x y<br />

6. 0 , 0 , e sin y Conservative<br />

7.<br />

2 2<br />

f 2 f g 3 2 3 x y y<br />

2 2<br />

2 x f ( x, y , z) x g( y, z) 3 y g( y, z) h( z) f ( x, y, z) x h( z)<br />

f<br />

z<br />

2 2 3y<br />

2<br />

2<br />

h ( z) 4 z h( z) 2 z C f ( x, y, z) x 2z C<br />

2<br />

f f g g<br />

x y y y<br />

8. y z f ( x, y, z) ( y z) x g( y, z) x x z z g( y, z) zy h( z)<br />

f<br />

z<br />

f ( x, y, z) ( y z) x zy h( z) x y h ( z) x y h ( z) 0 h( z) C f ( x, y, z)<br />

( y z)<br />

x zy C<br />

9.<br />

f y 2z y 2z f y 2z g y 2z<br />

g<br />

x y y y<br />

e f ( x, y, z) xe g( y, z) xe xe 0 f ( x, y, z)<br />

y 2z f y 2z y 2z y 2z<br />

( ) 2 ( ) 2 ( ) 0 ( ) ( , , )<br />

z<br />

xe h z xe h z xe h z h z C f x y z xe C<br />

f f g g<br />

x y y y<br />

10. y sin z f ( x, y, z) xy sin z g( y, z) x sin z x sin z 0 g( y, z) h( z)<br />

f<br />

z<br />

f ( x, y, z) xy sin z h( z) xy cos z h ( z) xy cos z h ( z) 0 h( z) C f ( x, y, z)<br />

xy sin z C<br />

Copyright<br />

2014 Pearson Education, Inc.

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