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Question
If the line joining two points A(2, 0) and B(3, 1) is rotated about A in anticlock wise direction through an angle of 15°. Find the equation of the line in new position.
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Solution
The slope of the line AB is `(1 - 0)/(3 - 2)` = 1 or tan 45° (Why?)
After rotation of the line through 15°
The slope of the line AC in new position is tan 60° = `sqrt(3)`
Therefore, the equation of the new line AC is
y – 0 = `sqrt(3) (x - 2)`
or `y - sqrt(3)x + 2sqrt(3)` = 0
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