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When the axes are rotated through an ang...

When the axes are rotated through an angle `60^(0)` the point P is changed as (3,4). Find original coordinates of P.

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To find the original coordinates of point P before the axes were rotated by an angle of \(60^\circ\), we can use the transformation formulas for rotation of axes. Let's denote the original coordinates of point P as \((x, y)\) and the new coordinates after rotation as \((x', y') = (3, 4)\). ### Step-by-Step Solution: 1. **Identify the Rotation Angle**: The angle of rotation is given as \( \theta = 60^\circ \). 2. **Use the Transformation Formulas**: The transformation formulas for rotating the axes are: \[ x = x' \cos \theta - y' \sin \theta \] \[ y = x' \sin \theta + y' \cos \theta \] 3. **Substitute the Values**: Substitute \(x' = 3\), \(y' = 4\), and \(\theta = 60^\circ\) into the formulas. We need the values of \(\cos 60^\circ\) and \(\sin 60^\circ\): \[ \cos 60^\circ = \frac{1}{2}, \quad \sin 60^\circ = \frac{\sqrt{3}}{2} \] 4. **Calculate the Original x-coordinate**: Using the formula for \(x\): \[ x = 3 \cdot \cos 60^\circ - 4 \cdot \sin 60^\circ \] \[ x = 3 \cdot \frac{1}{2} - 4 \cdot \frac{\sqrt{3}}{2} \] \[ x = \frac{3}{2} - 2\sqrt{3} \] 5. **Calculate the Original y-coordinate**: Using the formula for \(y\): \[ y = 3 \cdot \sin 60^\circ + 4 \cdot \cos 60^\circ \] \[ y = 3 \cdot \frac{\sqrt{3}}{2} + 4 \cdot \frac{1}{2} \] \[ y = \frac{3\sqrt{3}}{2} + 2 \] 6. **Final Result**: The original coordinates of point P before the rotation are: \[ (x, y) = \left(\frac{3}{2} - 2\sqrt{3}, \frac{3\sqrt{3}}{2} + 2\right) \]
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