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Consider two quadratic expressions f(x) ...

Consider two quadratic expressions `f(x) =ax^2+ bx + c and g (x)=ax^2+px+c,( a, b, c, p,q in R, b != p)` such that their discriminants are equal. If `f(x)= g(x)` has a root `x = alpha`, then

A

`alpha` will be AM of the roots of `f(x)=0` and `g(x)=0`

B

`alpha` will be AM of the roots of `f(x)=0`

C

`alpha` will be AM of the roots of `f(x)=0` or `g(x)=0`

D

`alpha` will be AM of the roots of `g(x)=0`

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To solve the problem step by step, we will analyze the given quadratic expressions and their properties. ### Step 1: Define the Quadratic Functions We have two quadratic functions: - \( f(x) = ax^2 + bx + c \) - \( g(x) = ax^2 + px + c \) ### Step 2: Calculate the Discriminants The discriminant \( D \) of a quadratic equation \( ax^2 + bx + c \) is given by: \[ D = b^2 - 4ac \] For \( f(x) \): \[ D_f = b^2 - 4ac \] For \( g(x) \): \[ D_g = p^2 - 4ac \] ### Step 3: Set the Discriminants Equal Since the discriminants are equal, we have: \[ b^2 - 4ac = p^2 - 4ac \] Cancelling \( -4ac \) from both sides gives: \[ b^2 = p^2 \] ### Step 4: Solve for \( b \) and \( p \) From \( b^2 = p^2 \), we can conclude: \[ b = p \quad \text{or} \quad b = -p \] Since it is given that \( b \neq p \), we must have: \[ b = -p \] ### Step 5: Set the Quadratic Functions Equal Now, we set \( f(x) \) equal to \( g(x) \): \[ ax^2 + bx + c = ax^2 + px + c \] Cancelling \( ax^2 \) and \( c \) from both sides results in: \[ bx = px \] This simplifies to: \[ (b - p)x = 0 \] ### Step 6: Identify the Roots Since \( b \neq p \), we must have: \[ x = 0 \] This means that \( x = 0 \) is a root of the equation \( f(x) = g(x) \). ### Step 7: Find the Other Roots Using \( b = -p \), we can rewrite the functions: - \( f(x) = ax^2 + bx + c \) - \( g(x) = ax^2 - bx + c \) The roots of \( f(x) = 0 \) are: \[ x = 0 \quad \text{and} \quad x = -\frac{b}{a} \] The roots of \( g(x) = 0 \) are: \[ x = 0 \quad \text{and} \quad x = \frac{p}{a} = -\frac{b}{a} \] ### Step 8: Relate the Roots to \( \alpha \) Since \( f(x) = g(x) \) has a root \( x = \alpha \), and we have established that \( \alpha \) must be the average of the roots of \( f(x) \) and \( g(x) \): \[ \alpha = \frac{-\frac{b}{a} + \left(-\frac{b}{a}\right)}{2} = -\frac{b}{2a} \] ### Conclusion Thus, the root \( \alpha \) is the arithmetic mean of the roots of \( f(x) = 0 \) and \( g(x) = 0 \).

To solve the problem step by step, we will analyze the given quadratic expressions and their properties. ### Step 1: Define the Quadratic Functions We have two quadratic functions: - \( f(x) = ax^2 + bx + c \) - \( g(x) = ax^2 + px + c \) ### Step 2: Calculate the Discriminants ...
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