Excel in math and science
Master concepts by solving fun, challenging problems.
It's hard to learn from lectures and videos
Learn more effectively through short, interactive explorations.
Used and loved by over 6 million people
Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.
Excel in math and science
Master concepts by solving fun, challenging problems.
It's hard to learn from lectures and videos
Learn more effectively through short, interactive explorations.
Used and loved by over 6 million people
Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.
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When a cannon is on the ground, the cannonball lands the farthest from the cannon if it's shot at a \(45^\circ\) angle.
Now, when the cannon is on a cliff, what shooting angle \(\theta\) makes the cannonball land the farthest?
Details and Assumptions:
- Neglect air resistance.
- The cannon shoots the cannonball at the same speed regardless of the angle of projection.
by
Pranshu Gaba
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Can \(\sqrt2, \sqrt3, \sqrt5\) all be numbers in an arithmetic progression?
Note: The three numbers do not need to be consecutive in the progression.
by
Shreyansh Mukhopadhyay
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A cube with side length 1 is sliced such that the cut is a regular hexagon (in red).
What is the side length of this regular hexagon (to 4 decimal places)?
by
Chan Lye Lee
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\[\large \sqrt[3]{x+\sqrt[3]{x+\sqrt[3]{x+\cdots}}}\ =\ \sqrt[3]{x\ \sqrt[3]{x\ \sqrt[3]{x\ldots}}}\]
The non-zero solution \(x\) of the equation above can be written as \(\frac{\sqrt{a}+\sqrt{b}}{2},\) where \(a\) and \(b\) are positive integers.
What is \(a+b?\)
by
Jian Hau Chooi
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The infinite Atwood’s machine shown has a string passing over each pulley, with one end attached to a mass and the other end attached to another pulley.
The masses are held fixed and then released simultaneously, and the acceleration of the top mass is \(\lambda g.\)
What is \(\lambda?\)
Details and Assumptions:
- All the masses are equal to \(M\).
- All the pulleys and strings are massless.
- \(g\) is the acceleration due to gravity.
by
Harsh Shrivastava
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