# If the roots of the quadratic equation # ax^2+bx+c=0# are imaginary then for all values of #a,b,c# and #x in R# then the nature of expression #a^2x^2+abx+ac# is?

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A. Positive

B. non-negative

C Negative

D may be positive, zero or negative

**Ans is A**

A. Positive

B. non-negative

C Negative

D may be positive, zero or negative

**Ans is A**

##### 1 Answer

Jul 18, 2017

See explanation...

#### Explanation:

To say that the roots of

#f(x) = ax^2+bx+c#

does not intersect the

Since this is described as a quadratic, we must have

So the whole of the parabola either lies on one side of the

When we multiply by

So the answer is indeed **A**.