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If the axes are rotated through an angle...

If the axes are rotated through an angle of `45^(@)` in the clockwise direction, the coordinates of a point in the new systeme are (0,-2) then its original coordinates are

A

`(sqrt(2),sqrt(2))`

B

`(-sqrt(2),sqrt(2))`

C

`(sqrt(2),-sqrt(2))`

D

`(-sqrt(2),-sqrt(2))`

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The correct Answer is:
To find the original coordinates of a point after the axes have been rotated through an angle of \(45^\circ\) in the clockwise direction, we can use the transformation formulas for coordinate rotation. ### Step-by-Step Solution: 1. **Identify the Given Information**: - The new coordinates after rotation are \((x', y') = (0, -2)\). - The angle of rotation \(\theta = 45^\circ\). 2. **Use the Rotation Formulas**: - The formulas to convert the new coordinates back to the original coordinates are: \[ x = x' \cos \theta - y' \sin \theta \] \[ y = x' \sin \theta + y' \cos \theta \] 3. **Substitute the Values**: - Substitute \(x' = 0\), \(y' = -2\), and \(\theta = 45^\circ\) into the formulas. Recall that \(\cos 45^\circ = \frac{1}{\sqrt{2}}\) and \(\sin 45^\circ = \frac{1}{\sqrt{2}}\). - For \(x\): \[ x = 0 \cdot \cos 45^\circ - (-2) \cdot \sin 45^\circ \] \[ x = 0 - (-2) \cdot \frac{1}{\sqrt{2}} = 2 \cdot \frac{1}{\sqrt{2}} = \frac{2}{\sqrt{2}} = \sqrt{2} \] - For \(y\): \[ y = 0 \cdot \sin 45^\circ + (-2) \cdot \cos 45^\circ \] \[ y = 0 - 2 \cdot \frac{1}{\sqrt{2}} = -\frac{2}{\sqrt{2}} = -\sqrt{2} \] 4. **Final Result**: - The original coordinates are \((x, y) = (\sqrt{2}, -\sqrt{2})\). ### Summary: Thus, the original coordinates of the point before the rotation are \((\sqrt{2}, -\sqrt{2})\). ---

To find the original coordinates of a point after the axes have been rotated through an angle of \(45^\circ\) in the clockwise direction, we can use the transformation formulas for coordinate rotation. ### Step-by-Step Solution: 1. **Identify the Given Information**: - The new coordinates after rotation are \((x', y') = (0, -2)\). - The angle of rotation \(\theta = 45^\circ\). ...
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