A ladder leans against a vertical wall on horizontal ground. The base of the ladder slides away from the wall at a constant rate of .
Find the rate of change of the area of the right triangle formed by the ladder, the wall, and the ground at the instant when the base is from the wall.
[6]A ladder of length slides against a vertical wall. The base of the ladder moves away from the wall at a constant rate of . Find the rate of change of the perimeter of the triangle formed by the ladder, the wall, and the ground at the instant when the base is from the wall.
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