The quadratic equation p(x) = 0 with real coefficients has purely imag...
Hence real or purely imaginary number can not satisfy P(P(x)) = 0.
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The quadratic equation p(x) = 0 with real coefficients has purely imag...
Explanation:
To understand why the correct answer is option 'D', let's analyze the given information step by step.
1. The quadratic equation p(x) = 0 has purely imaginary roots.
A quadratic equation with real coefficients can be written in the form:
p(x) = ax^2 + bx + c = 0
where a, b, and c are real numbers.
If the quadratic equation has purely imaginary roots, it means that the discriminant of the equation is negative. The discriminant is given by:
D = b^2 - 4ac
If D < 0,="" the="" roots="" of="" the="" equation="" will="" be="" purely="" />
2. p(p(x)) = 0
Now, let's consider the equation p(p(x)) = 0. To find the roots of p(p(x)), we need to find the values of x that satisfy this equation.
Let's substitute p(x) with y:
p(y) = 0
Now, we have the equation p(y) = 0, which is a quadratic equation. We know that this equation has purely imaginary roots.
3. Analyzing p(y) = 0
Since p(y) = 0 has purely imaginary roots, the discriminant of p(y) must be negative:
D' = b'^2 - 4a'c' < />
where a', b', and c' are the coefficients of the quadratic equation p(y) = 0.
4. Analyzing p(p(x)) = 0
Let's substitute y back with p(x) in the discriminant equation:
D' = b'^2 - 4a'c' = (b(p(x)))^2 - 4(a(p(x))(c(p(x))))
Since p(y) = 0 has purely imaginary roots, we know that D' < 0.="" therefore,="" the="" discriminant="" of="" p(p(x))="0" is="" />
5. Conclusion
From our analysis, we can conclude that the equation p(p(x)) = 0 has no real roots or purely imaginary roots. Therefore, the correct answer is option 'D' - neither real nor purely imaginary roots.
This conclusion is based on the fact that if the quadratic equation p(x) = 0 has purely imaginary roots, then any composition of p(x) will also have neither real nor purely imaginary roots.
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