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If veca and vecb are two nonzero vectors...

If `veca and vecb` are two nonzero vectors such that `|vecaxxvecb|=veca.vecb` then find the angle between `veca and vecb.`

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To solve the problem, we need to find the angle between two nonzero vectors \(\vec{a}\) and \(\vec{b}\) given the condition that the magnitude of their cross product is equal to their dot product. ### Step-by-Step Solution: 1. **Understanding the Given Condition**: We are given that: \[ |\vec{a} \times \vec{b}| = \vec{a} \cdot \vec{b} \] 2. **Using the Formulas for Cross Product and Dot Product**: We know the formulas for the magnitudes of the cross product and the dot product: - The magnitude of the cross product: \[ |\vec{a} \times \vec{b}| = |\vec{a}| |\vec{b}| \sin \theta \] - The dot product: \[ \vec{a} \cdot \vec{b} = |\vec{a}| |\vec{b}| \cos \theta \] 3. **Setting the Two Expressions Equal**: Now, substituting these formulas into the given condition: \[ |\vec{a}| |\vec{b}| \sin \theta = |\vec{a}| |\vec{b}| \cos \theta \] 4. **Dividing Both Sides by \(|\vec{a}| |\vec{b}|\)**: Since \(\vec{a}\) and \(\vec{b}\) are nonzero vectors, we can safely divide both sides by \(|\vec{a}| |\vec{b}|\): \[ \sin \theta = \cos \theta \] 5. **Using the Identity**: The equation \(\sin \theta = \cos \theta\) can be rewritten using the tangent function: \[ \tan \theta = 1 \] 6. **Finding the Angle**: The angle \(\theta\) for which \(\tan \theta = 1\) is: \[ \theta = \frac{\pi}{4} \text{ radians} \quad \text{or} \quad 45^\circ \] ### Final Answer: The angle between the vectors \(\vec{a}\) and \(\vec{b}\) is: \[ \theta = 45^\circ \quad \text{or} \quad \frac{\pi}{4} \text{ radians} \]
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