Determine all values of the real parameter for which the equation
has no real solutions.
Solution
Let us consider the quadratic equation:
This equation has no real solutions if and only if its discriminant is negative.
The discriminant is:
We require:
Divide both sides by :
But the quadratic has discriminant:
So is always positive for all real .
Therefore, there is **no real value of ** for which the equation has no real solutions.
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