Let f (x) = ax2 + bx + c, a, b, c Ïµ R. If f (x) Takes Real Values For Real Values Of x and Non – Real Values For Non – Real Values Of x, Then.

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Question

Let f (x) = ax2 + bx + cabc Ïµ R. if f (x) takes real values for real values of x and non – real values for non – real values of x, then.

Solution

Correct option is

a = 0

Suppose a ≠ 0. We rewrite f (x) as follows:

                         

            

                                  

Which is a real number This is against the hypothesis. Therefore,

 a = 0.

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