If , where and be the complex numbers such that that and . If for all , show that for all real .

- Apr 30th 2009, 06:29 AMfardeen_genShow that f(x) + f'(x) + f"(x) > 0 for all real x(Complex numbers)?
If , where and be the complex numbers such that that and . If for all , show that for all real .

- Apr 30th 2009, 12:56 PMOpalg
You have mixed up two separate problems. The sentence in blue is completely irrelevant to the problem contained in the second sentence.

The conditions for the quadratic polynomial to be always positive are that and . If f(x) satisfies those conditions then it easy to check that satisfies the same conditions.