/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 15 Compute the following cross prod... [FREE SOLUTION] | 91Ó°ÊÓ

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Compute the following cross products. Then make a sketch showing the two vectors and their cross product. $$\mathbf{j} \times \mathbf{k}$$

Short Answer

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Question: Compute the cross product of the vectors j and k. Represent the obtained cross product, along with the original vectors, in a sketch. Answer: The cross product of vectors j and k is i. In the sketch, vector j should be drawn along the Y-axis, vector k along the Z-axis, and their cross product, vector i, along the X-axis in a 3D coordinate system.

Step by step solution

01

Compute the cross product

To compute the cross product between vectors j and k, we simply use the standard formula for cross products. Note that we have: $$\mathbf{i} \equiv (1,0,0)$$ $$\mathbf{j} \equiv (0,1,0)$$ $$\mathbf{k} \equiv (0,0,1)$$ Now the cross product between two 3D vectors (a,b,c) and (d,e,f) is given by: $$(a,b,c) \times (d,e,f) = (bf - ce, cd - af, ae - bd)$$ Applying this formula to the vectors \(\mathbf{j}\) and \(\mathbf{k}\), we get: $$(0,1,0) \times (0,0,1) = (1 \cdot 0 - 0 \cdot 0, 0 \cdot 1 - 0 \cdot 0, 0 \cdot 0 - 1 \cdot 0) = (0,0,0) - (0,1,0)$$ So, the cross product \(\mathbf{j} \times \mathbf{k} = \mathbf{i}\).
02

Make a sketch

To create a sketch, draw the 3D coordinate system with mutually perpendicular axes: X-axis, Y-axis, and Z-axis, representing the i, j, and k vectors respectively. Draw the vector \(\mathbf{j}\) along the Y-axis starting from the origin, and vector \(\mathbf{k}\) along the Z-axis starting from the origin. The cross product, vector \(\mathbf{i}\), will lie on the X-axis. The final sketch should clearly show the two vectors \(\mathbf{j}\) and \(\mathbf{k}\), as well as their cross product, vector \(\mathbf{i}\), in the 3D coordinate system.

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