A circle of radius k units is drawn with (0,0) as the center. Diameters to this circle: X axis, Y axis, and |y|=|x| are drawn.
Find the probability that product of slopes of 2 diameters chosen at random is -1.
a.)1/6
b.)2/6
c.)3/6
d.)None of the above
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The diameters are...jkaustubh wrote:A circle of radius k units is drawn with (0,0) as the center. Diameters to this circle: X axis, Y axis, and |y|=|x| are drawn. Find the probability that product of slopes of 2 diameters chosen at random is -1.
- 1. X-axis --> slope = 0
2. Y-axis --> slope = infinity
3. x = y --> slope = 1
4. x = -y --> slope = -1
Among them only the product of slopes of 3 and 4 will be -1.
Hence, required probability = 1/6
The correct answer is A.
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