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Use the geometric definition to find (i→ j→)×(i→−j→).

User Esen
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Final answer:

The cross product of the vectors (i→ j→)×(i→−j→) is calculated using the properties of cross products and is found to be -k.

Step-by-step explanation:

We are asked to find the cross product (i→ j→)×(i→−j→).

Using the properties of cross products and the geometric definition, we know that:

  • i×i = j×j = k×k = 0, because the cross product of any vector with itself is zero.
  • For any pair of different unit vectors, the result is the third unit vector, following a cyclic order.
  • If the two unit vectors are reversed in order, the resulting unit vector is negative.

Now, applying these rules:

  • i×i = 0 and j×j = 0, since they are the same unit vectors.
  • Then we have i×(-j) = -(i×j).
  • From the cyclic order (i, j, k), we have i×j = k, so i×(-j) = -k.
  • Therefore, the result is 0i + 0j + (-k), which simplifies to -k.

The cross product of the vectors (i→ j→)×(i→−j→) is -k.

User Fabians
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