Probability obtuse triangle - simple one

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wuid
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Homework Statement



The two sides lengths of a triangle is exponentially distributed. (not so important for my question)

The angle between the sides is uniformly distributed [0,2∏]

c) explain why the probability to get obtuse triangle is greater then 0.5

The Attempt at a Solution



i don't understand why it is grater then 0.5 and not exactly 0.5...
 
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wuid said:

Homework Statement



The two sides lengths of a triangle is exponentially distributed. (not so important for my question)

The angle between the sides is uniformly distributed [0,2∏]

c) explain why the probability to get obtuse triangle is greater then 0.5

The Attempt at a Solution



i don't understand why it is grater then 0.5 and not exactly 0.5...

Hi wuid! :smile:

Looks like the question is the probability to get any obtuse angle in the triangle (also considering the other 2 angles)...
 
i am missing something... to get obtuse triangle is that the probability of the angle to be between [∏/2,3∏/2] so what i thought is : what is the probability that θ is within the II or III quarter of the plane so it is P(II)+P(III) = 0.25 + 0.25 = 0.5.

where i am wrong ?
 
obtuse triangle :)
so without calculation, can i say that the probability is greater than 0.5, because that i get obtuse angle with probability 0.5 but i need to add a measure of probability that the other two angles would sum up with the first on to 180 degrees ? gives that the triangle is obtuse.
 
I never see the all picture...
thank you !