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If a^(2) + (1)/(a^(2))= 23 and a ne 0, f...

If `a^(2) + (1)/(a^(2))= 23 and a ne 0`, find the value of `a^(3) + (1)/(a^(3))`

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To solve the problem, we will follow these steps: ### Step 1: Given Information We start with the equation: \[ a^2 + \frac{1}{a^2} = 23 \] ### Step 2: Find \(a + \frac{1}{a}\) We know that: \[ \left(a + \frac{1}{a}\right)^2 = a^2 + 2 + \frac{1}{a^2} \] Thus, we can rearrange this to find \(a + \frac{1}{a}\): \[ \left(a + \frac{1}{a}\right)^2 = a^2 + \frac{1}{a^2} + 2 \] Substituting the known value: \[ \left(a + \frac{1}{a}\right)^2 = 23 + 2 = 25 \] Taking the square root: \[ a + \frac{1}{a} = \sqrt{25} = 5 \] ### Step 3: Find \(a^3 + \frac{1}{a^3}\) We will use the identity: \[ a^3 + \frac{1}{a^3} = \left(a + \frac{1}{a}\right)^3 - 3\left(a + \frac{1}{a}\right) \] Substituting \(a + \frac{1}{a} = 5\): \[ a^3 + \frac{1}{a^3} = 5^3 - 3 \times 5 \] Calculating \(5^3\): \[ 5^3 = 125 \] Calculating \(3 \times 5\): \[ 3 \times 5 = 15 \] Now substituting these values back: \[ a^3 + \frac{1}{a^3} = 125 - 15 = 110 \] ### Final Answer Thus, the value of \(a^3 + \frac{1}{a^3}\) is: \[ \boxed{110} \] ---
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