**1. The problem statement, all variables and given/known data**

You’re given a cannon that allows you to fix the initial velocity and the shooting angle of a projectile that should be embedded on the side of a mountain [itex]l[/itex] meters away.

What is the minimum velocity for you to embed the projectile at an angle of [itex] \frac{\pi}{4}[/itex]?

**3. The attempt at a solution**

I’m not quite sure how to tackle the problem, I do know I have to optimize somehow the velocity but I don’t know which expression should I take the derivative of. All help will be greatly appreciated.

Best,

M.

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