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The difference of two unit vectors is fo...

The difference of two unit vectors is found to have a magnitude of unity . The angle between them is

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To solve the problem step by step, we will use the properties of vectors and the information given in the question. ### Step 1: Define the unit vectors Let the two unit vectors be represented as \( \hat{a} \) and \( \hat{b} \). ### Step 2: Write the equation for the magnitude of their difference We know that the magnitude of the difference of the two unit vectors is given as: \[ |\hat{a} - \hat{b}| = 1 \] ### Step 3: Square both sides of the equation To eliminate the square root, we square both sides: \[ |\hat{a} - \hat{b}|^2 = 1^2 \] This gives us: \[ |\hat{a} - \hat{b}|^2 = 1 \] ### Step 4: Expand the left-hand side using the formula for the magnitude of a vector Using the formula for the magnitude of the difference of two vectors, we have: \[ |\hat{a} - \hat{b}|^2 = |\hat{a}|^2 + |\hat{b}|^2 - 2 |\hat{a}| |\hat{b}| \cos(\theta) \] where \( \theta \) is the angle between the two vectors. ### Step 5: Substitute the magnitudes of the unit vectors Since both \( \hat{a} \) and \( \hat{b} \) are unit vectors, their magnitudes are 1: \[ |\hat{a}|^2 = 1 \quad \text{and} \quad |\hat{b}|^2 = 1 \] Substituting these values into the equation gives: \[ 1 + 1 - 2 \cdot 1 \cdot 1 \cdot \cos(\theta) = 1 \] This simplifies to: \[ 2 - 2 \cos(\theta) = 1 \] ### Step 6: Rearrange the equation Rearranging the equation, we have: \[ 2 - 1 = 2 \cos(\theta) \] which simplifies to: \[ 1 = 2 \cos(\theta) \] ### Step 7: Solve for \( \cos(\theta) \) Dividing both sides by 2 gives: \[ \cos(\theta) = \frac{1}{2} \] ### Step 8: Determine the angle \( \theta \) The angle \( \theta \) for which \( \cos(\theta) = \frac{1}{2} \) is: \[ \theta = 60^\circ \quad \text{or} \quad \theta = \frac{\pi}{3} \text{ radians} \] ### Final Answer Thus, the angle between the two unit vectors is \( 60^\circ \) or \( \frac{\pi}{3} \) radians. ---
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