Has the age at which we teach Mathematics changed over the last two centuries?

Well It depends on what you think about mathematics. Generally, Through history we all learn mathematics from a very young age because We learn counting.

Now Isaac newton didn't learn calculus in University because he is the one who came up with calculus in the first place and therefore, Nowadays, The mathematical curriculum for university involves way more advanced mathematics compared to 100 years back. Now we have graph theory , combinatorics , Modern Algebra , Number theory and topology. This is way more math than they did 100 years ago, I would say even Einstein didn't do a lot of math compared to People doing research now.

In the future, I think people will learn more about modular arithmetic and number theory earlier than they do nowadays.

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Let $D$ be a bounded domain (open connected) in $ \mathbb C$ and assume that complement of $D$ is connected.Then show that $\partial D$ is connected

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Newton iteration on Riemannian manifolds

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same distance from a point to 2 non-parallel lines

$2^i - 2293$ is always composite?

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