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If f(x)=2x^(3)-3x^(2)+1 then number of d...

If `f(x)=2x^(3)-3x^(2)+1` then number of distinct real solution (s) of the equation `f(f(x))=0` is/(are) `k` then `(7k)/(10^(2))` is equal to_______

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To solve the problem step by step, we need to find the number of distinct real solutions of the equation \( f(f(x)) = 0 \), where \( f(x) = 2x^3 - 3x^2 + 1 \). ### Step 1: Find the roots of \( f(x) = 0 \) We start by solving the equation \( f(x) = 0 \): \[ f(x) = 2x^3 - 3x^2 + 1 = 0 \] ### Step 2: Find the derivative \( f'(x) \) To determine the nature of the roots, we first find the derivative: \[ f'(x) = \frac{d}{dx}(2x^3 - 3x^2 + 1) = 6x^2 - 6x = 6x(x - 1) \] ### Step 3: Find critical points Setting the derivative equal to zero gives us the critical points: \[ 6x(x - 1) = 0 \implies x = 0 \text{ or } x = 1 \] ### Step 4: Analyze the behavior of \( f(x) \) Now we analyze the function \( f(x) \) at the critical points and the limits: - As \( x \to -\infty \), \( f(x) \to -\infty \) - At \( x = 0 \): \[ f(0) = 2(0)^3 - 3(0)^2 + 1 = 1 \] - At \( x = 1 \): \[ f(1) = 2(1)^3 - 3(1)^2 + 1 = 2 - 3 + 1 = 0 \] - As \( x \to +\infty \), \( f(x) \to +\infty \) ### Step 5: Determine the number of roots Since \( f(x) \) is a cubic polynomial, it can have at most 3 real roots. We know: - \( f(0) = 1 > 0 \) - \( f(1) = 0 \) (one root) - The function changes from negative to positive as \( x \) increases from \( -\infty \) to \( 0 \) and again from \( 1 \) to \( +\infty \). Using the Intermediate Value Theorem, we can conclude that there is one root between \( -\infty \) and \( 0 \) and one root between \( 0 \) and \( 1 \). Therefore, \( f(x) = 0 \) has 3 distinct real roots. ### Step 6: Find \( k \) Let \( k \) be the number of distinct real solutions of \( f(x) = 0 \): \[ k = 3 \] ### Step 7: Find \( f(f(x)) = 0 \) Since \( f(x) = 0 \) has 3 distinct roots, we need to find \( f(f(x)) = 0 \). Each root of \( f(x) = 0 \) can be plugged back into \( f(x) \), which means we need to find the number of distinct solutions to \( f(x) = r \) for each root \( r \). Since \( f(x) \) has 3 distinct roots, and since \( f(x) \) is a cubic polynomial, it can take each value (including the roots) at most 3 times. Therefore, the total number of distinct solutions to \( f(f(x)) = 0 \) is: \[ 3 \text{ (roots of } f(x) = 0\text{)} \times 3 \text{ (each root can be achieved 3 times)} = 9 \] ### Step 8: Calculate \( \frac{7k}{10^2} \) Now we calculate: \[ \frac{7k}{10^2} = \frac{7 \times 3}{100} = \frac{21}{100} = 0.21 \] ### Final Answer Thus, the value of \( \frac{7k}{10^2} \) is: \[ \boxed{0.21} \]

To solve the problem step by step, we need to find the number of distinct real solutions of the equation \( f(f(x)) = 0 \), where \( f(x) = 2x^3 - 3x^2 + 1 \). ### Step 1: Find the roots of \( f(x) = 0 \) We start by solving the equation \( f(x) = 0 \): \[ f(x) = 2x^3 - 3x^2 + 1 = 0 ...
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