Vector Integration Homework: Evaluate Integrals A⋅B & A×B

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To evaluate the integrals of vector functions A(t) and B(t), first calculate the dot product A ⋅ B by using the formula Ai*Bi + Aj*Bj + Ak*Bk, and then integrate over the interval from 0 to 2. For the cross product A × B, set up a matrix with unit vectors i, j, k in the first row, followed by the components of A in the second row and B in the third row. After determining the cross product, integrate the result over the same interval. The discussion emphasizes the importance of correctly applying the formulas for both operations. The user successfully solved the problem with this guidance.
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Homework Statement



If A(t) = t i - t2 j + (t - 1) k and B(t) = 2t2 i + 6t k, evaluate (a) \int^{2}_{0}A \cdot B dt, (b) \int^{2}_{0}A \times B dt.

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The Attempt at a Solution


Help me please because I don't know how to solve this problem. Thanks!

Looking forward to your responses.
 
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Take the dot product for the first and then integrate and take the cross product for the second. Dot product remember is Ai*Bi + Aj*Bj + Ak*Bk. For cross product, set up a matrix with i j k in row one followed by the i j k of a in row 2 and i j k of b in row 3
 
Dustinsfl said:
Take the dot product for the first and then integrate and take the cross product for the second. Dot product remember is Ai*Bi + Aj*Bj + Ak*Bk. For cross product, set up a matrix with i j k in row one followed by the i j k of a in row 2 and i j k of b in row 3

Thanks! I've got the answer..:smile:
 
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