Assignment 17

course Mth 272

w˕KzQWwvDassignment #017

017.

Applied Calculus II

03-15-2009

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20:34:16

Query problem 6.3.18 integrate 3/(x ^ 2 - 3x)

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RESPONSE -->

first factor denom

= A/x + B/x-3

3= A(x-3) + B(x) first find A

3= A(3-3) + B(3)

3=B(3)

B=1

3= A(0-3) + B(0)

3=A(-3)

A=-1

1/x - 1/x-3 then integrate

ln(x/x-3) +c

Good.

confidence assessment: 3

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20:34:23

What is your integral?

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RESPONSE -->

answered

confidence assessment: 3

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20:34:31

Explain how you used partial fractions to obtain your result.

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RESPONSE -->

answered

confidence assessment: 3

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20:51:25

Query problem 6.3.29 (was 6.3.27) integrate (x+2) / (x^2 - 4x)

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RESPONSE -->

factor first

x(x-4)

A/x + b/x-4 = x^2/x(x-4)

A(x-4) + B(x) = x+2

Ax-4A + Bx= x+2

(A+B)x - 4A = x+2

A= -1/2 B = 3/2

~ -1/2xdx + ~ 3/2(x-4)dx

-1/2~1/xdx+ 3/2~(1/x-4)dx

3/2ln(x-4) - 1/2 ln(x)+c

1/2[(3ln(x-4) - ln(x)] + c

confidence assessment: 3

Good. Your result can be expressed as

1/2 ln ( |x-4|^3 / | x | ) + c **

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20:51:33

What is your integral?

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RESPONSE -->

answered

confidence assessment: 3

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20:51:44

Explain how you used partial fractions to obtain your result.

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RESPONSE -->

answered

confidence assessment: 3

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20:52:07

Query Add comments on any surprises or insights you experienced as a result of this assignment.

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RESPONSE -->

I understood this one well. It was easy to understand in the book.

confidence assessment: 3

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&#Good responses. See my notes and let me know if you have questions. &#