The expression has always the same sign as, if |
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a) |
b) |
c) |
d) |

The expression has always the same sign as, if |
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a) |
b) |
c) |
d) |

1 Answer

127 votes

**(b)**

Let Then,

Thus, the curve meets -axis at

If then by hypothesis This means that the curve does not meet -axis

If then by hypothesis, which means that the curve is always below -axis and so it does not intersect with -axis

Thus, in both the cases does not intersect with -axis for any real

Hence, i.e. has imaginary roots and so we have

127 votes

127