Problems

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Found: 16

A student did not notice the multiplication sign between two three-digit numbers and wrote one six-digit number, which turned out to be exactly seven times their product. Determine these numbers.

The student did not notice the multiplication sign between two seven-digit numbers and wrote one fourteen-digit number, which turned out to be three times bigger than their product. Determine these numbers.

Solve the equation \(3x + 5y = 7\) in integers. Make sure that you’ve found all integer solutions.

Recall that a natural number \(x\) is called prime if \(x\) has no divisors except \(1\) and itself. Solve the equation with prime numbers \(pqr = 7(p + q + r)\).

How many rational terms are contained in the expansion of

a) \((\sqrt 2 + \sqrt[4]{3})^{100}\);

b) \((\sqrt 2 + \sqrt[3]{3})^{300}\)?