writing assignment 1

# writing assignment 1 - x for “u” and x 2 dx for...

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Math 151 Writing Assignment #1 Scott B. Roberts The objective of performing integration by parts is to evaluate the integral by simplifying it through braking it into different parts. It is necessary to initially choose a part for “u” as well as the other part for “dv”. When choosing “dv” one should pick the part that is easiest to integrate, which will give you your “v” value. The correct option for “u” is the part that is easiest to differentiate. You also want to keep in mind that you want your “du” to be in simpler form than the “u”. For example, if you have the integral x 2 e x dx we have some options. Say we pick e
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Unformatted text preview: x for “u” and x 2 dx for “dv”. The derivative for e x is e x , so this is an acceptable choice for “u”. This leaves us with x 2 dx for “dv”. Next we integrate x 2 dx we end up with 1/3 x 3 dx. When we proceed with our problem by following the formula of: udv = uv- vdu. We find that the power of x has increased, therefore making our problem more difficult than it originally was. This is a poor choice for “dv”. If we choose x 2 for “u” and e x dx for “dv” then the derivative of x 2 is 2x and the integral of e x dx is e x . So when we integrate by parts, our problem is easier after we apply the formula....
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## This note was uploaded on 09/20/2008 for the course MATH 151 taught by Professor Bray during the Spring '07 term at Mesa CC.

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