What are the results of integrating the dot and cross products of two vectors?

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The discussion focuses on evaluating the dot and cross products of two vector functions, A(t) = t i - t² j + (t - 1) k and B(t) = 2t² i + 6t k. The integral of the dot product over the interval from 0 to 2 results in the expression 2t³ + 6t² - 6t, which can be integrated to yield a specific numerical result. The cross product yields -6t³ i + (2t³ - 8t²) j + 2t⁴ k, which also requires integration over the same interval. The discussion emphasizes the necessity of showing initial attempts at solving the problem to receive assistance.

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If A(t) = t i - t2 j + (t - 1) k and B(t) = 2t2 i + 6t k, evaluate (a) \int^{2}_{0}A \cdot Bdt , (b) \int^{2}_{0}A \times B dt.
 
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I have no idea!

Can you help me out, by SHOWING WHAT YOU HAVE DONE SO FAR?
 
yusukered07 said:
1. If A (t) = t i - t2j + (t -1) k, evaluate (b) \int^{2}_{0} A
Integral of t = t2/2 = 2
Integral of t2 = t3/3 = 8/3
Integral of (t-1)=t2/2 - t = 0

Net result 2i -(8/3)j
 
mathman said:
Integral of t = t2/2 = 2
Integral of t2 = t3/3 = 8/3
Integral of (t-1)=t2/2 - t = 0

Net result 2i -(8/3)j

Sorry for giving a wrong problem...
 
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yusukered07 said:
If A(t) = t i - t2 j + (t - 1) k and B(t) = 2t2 i + 6t k, evaluate (a) \int^{2}_{0}A \cdot Bdt , (b) \int^{2}_{0}A \times B dt.

You need to show an attempt at solving the problem before receiving help!

Start by evaluating A·B and AxB.
 
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Redbelly98 said:
Moderator's note: thread moved from "Calculus & Analysis"

Homework assignments or any textbook style exercises are to be posted in the appropriate forum in our https://www.physicsforums.com/forumdisplay.php?f=152" area. This should be done whether the problem is part of one's assigned coursework or just independent study.


You need to show an attempt at solving the problem before receiving help!

Start by evaluating A·B and AxB.


Yeah... That's the process I've made... Then I integrate them with respect to t and evaluate from 0 to 2
 
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For the dot product of A and B, I obtained 2*t3+6*t2-6*t. Then integrate that from 0 to 2.

For the cross product, I obtained -6*t3i+(2*t3-8*t2)j+2*t4k.
 

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