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If m^(2)-4m+1=0, then the value of (m^(3...

If `m^(2)-4m+1=0`, then the value of `(m^(3)+(1)/(m^(3)))` is :

A

48

B

52

C

64

D

none of these

Text Solution

AI Generated Solution

The correct Answer is:
To solve the equation \( m^2 - 4m + 1 = 0 \) and find the value of \( m^3 + \frac{1}{m^3} \), we can follow these steps: ### Step 1: Solve the quadratic equation We start with the equation: \[ m^2 - 4m + 1 = 0 \] We can use the quadratic formula \( m = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \), where \( a = 1, b = -4, c = 1 \). Calculating the discriminant: \[ b^2 - 4ac = (-4)^2 - 4 \cdot 1 \cdot 1 = 16 - 4 = 12 \] Now substituting into the quadratic formula: \[ m = \frac{4 \pm \sqrt{12}}{2} = \frac{4 \pm 2\sqrt{3}}{2} = 2 \pm \sqrt{3} \] Thus, the roots are: \[ m_1 = 2 + \sqrt{3} \quad \text{and} \quad m_2 = 2 - \sqrt{3} \] ### Step 2: Find \( m + \frac{1}{m} \) Using the relationship derived from the quadratic equation, we can express \( m + \frac{1}{m} \): \[ m + \frac{1}{m} = 4 \] This is derived from dividing the original equation by \( m \). ### Step 3: Find \( m^3 + \frac{1}{m^3} \) We can use the identity: \[ m^3 + \frac{1}{m^3} = \left(m + \frac{1}{m}\right)^3 - 3\left(m + \frac{1}{m}\right) \] Substituting \( m + \frac{1}{m} = 4 \): \[ m^3 + \frac{1}{m^3} = 4^3 - 3 \cdot 4 \] Calculating \( 4^3 \): \[ 4^3 = 64 \] Now substituting back: \[ m^3 + \frac{1}{m^3} = 64 - 12 = 52 \] ### Final Answer Thus, the value of \( m^3 + \frac{1}{m^3} \) is: \[ \boxed{52} \]
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