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Let f(x)=x^(2)+2px+2q^(2) and g(x)=-x^(2...

Let `f(x)=x^(2)+2px+2q^(2) and g(x)=-x^(2)-2qx+q^(2)` (where `q ne0`). If `x in R` and the minimum value of `f(x)` is equal to the maximum value of `g(x)`, then the value of `(p^(2))/(q^(2))` is equal to

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To solve the problem, we need to find the value of \( \frac{p^2}{q^2} \) given the functions: \[ f(x) = x^2 + 2px + 2q^2 \] \[ g(x) = -x^2 - 2qx + q^2 \] where \( q \neq 0 \). We know that the minimum value of \( f(x) \) is equal to the maximum value of \( g(x) \). ### Step 1: Find the minimum value of \( f(x) \) The function \( f(x) \) is a quadratic function that opens upwards (since the coefficient of \( x^2 \) is positive). The minimum value of a quadratic function \( ax^2 + bx + c \) can be found using the formula: \[ \text{Minimum value} = -\frac{D}{4a} \] where \( D \) is the discriminant given by \( D = b^2 - 4ac \). For \( f(x) \): - \( a = 1 \) - \( b = 2p \) - \( c = 2q^2 \) Calculating the discriminant \( D \): \[ D = (2p)^2 - 4 \cdot 1 \cdot 2q^2 = 4p^2 - 8q^2 \] Now, substituting into the minimum value formula: \[ \text{Minimum value of } f(x) = -\frac{4p^2 - 8q^2}{4} = -p^2 + 2q^2 \] ### Step 2: Find the maximum value of \( g(x) \) The function \( g(x) \) is a quadratic function that opens downwards (since the coefficient of \( x^2 \) is negative). The maximum value of a quadratic function \( ax^2 + bx + c \) can be found using the formula: \[ \text{Maximum value} = -\frac{D}{4a} \] For \( g(x) \): - \( a = -1 \) - \( b = -2q \) - \( c = q^2 \) Calculating the discriminant \( D \): \[ D = (-2q)^2 - 4 \cdot (-1) \cdot q^2 = 4q^2 + 4q^2 = 8q^2 \] Now, substituting into the maximum value formula: \[ \text{Maximum value of } g(x) = -\frac{8q^2}{4 \cdot (-1)} = 2q^2 \] ### Step 3: Set the minimum value of \( f(x) \) equal to the maximum value of \( g(x) \) From the problem statement, we have: \[ -p^2 + 2q^2 = 2q^2 \] ### Step 4: Solve for \( p^2 \) Rearranging the equation gives: \[ -p^2 = 0 \] Thus, \[ p^2 = 0 \] ### Step 5: Find \( \frac{p^2}{q^2} \) Since \( p^2 = 0 \), we can substitute into the expression: \[ \frac{p^2}{q^2} = \frac{0}{q^2} = 0 \] ### Conclusion The value of \( \frac{p^2}{q^2} \) is: \[ \boxed{0} \]
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