Case 1: When \(x^2 - 3x - 10 = 0\) and \(x^2 - 10 \ne 0\)
Solve the quadratic: \[ x^2 - 3x - 10 = 0 \] Factorizing: \[ (x - 5)(x + 2) = 0 \] So, \(x = 5\) or \(x = -2\)
Now check that neither value satisfies \(x^2 - 10 = 0\), which is true, so both values are valid.
Case 2: When \(x^2 - 10 = 1\)
Then: \[ x^2 = 11 \] This has no integer solutions. So no values of \(x\) from this case.
Case 3: When \(x^2 - 10 = -1\) and \(x^2 - 3x - 10\) is even
Then: \[ x^2 = 9 \] So: \[ (x + 3)(x - 3) = 0 \Rightarrow x = -3 \text{ or } x = 3 \]
Now check if \(x^2 - 3x - 10\) is even for both values:
So both values are valid.
Conclusion: The valid integer solutions for \(x\) are: \[ x = -3, -2, 3, 5 \] That is, a total of 4 values satisfy the conditions.
For any natural number $k$, let $a_k = 3^k$. The smallest natural number $m$ for which \[ (a_1)^1 \times (a_2)^2 \times \dots \times (a_{20})^{20} \;<\; a_{21} \times a_{22} \times \dots \times a_{20+m} \] is: