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The eccentricity of the ellipse (x^(2))/...

The eccentricity of the ellipse `(x^(2))/(49) +(y^(2))/(36) = 1 ` is `(sqrt(5))/(3)`.

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To find the eccentricity of the ellipse given by the equation \[ \frac{x^2}{49} + \frac{y^2}{36} = 1, \] we will follow these steps: ### Step 1: Identify the values of \(a^2\) and \(b^2\) The standard form of the ellipse is \[ \frac{x^2}{a^2} + \frac{y^2}{b^2} = 1. \] From the given equation, we can identify: - \(a^2 = 49\) - \(b^2 = 36\) ### Step 2: Calculate \(a\) and \(b\) Now, we will find \(a\) and \(b\): \[ a = \sqrt{49} = 7, \] \[ b = \sqrt{36} = 6. \] ### Step 3: Use the formula for eccentricity \(e\) The formula for the eccentricity \(e\) of an ellipse is given by: \[ e = \sqrt{1 - \frac{b^2}{a^2}}. \] ### Step 4: Substitute the values of \(a^2\) and \(b^2\) Now, substituting the values we found: \[ e = \sqrt{1 - \frac{36}{49}}. \] ### Step 5: Simplify the expression Calculating the fraction: \[ \frac{36}{49} = 0.734693877. \] Now, subtracting from 1: \[ 1 - \frac{36}{49} = \frac{49 - 36}{49} = \frac{13}{49}. \] ### Step 6: Take the square root Now, we take the square root: \[ e = \sqrt{\frac{13}{49}} = \frac{\sqrt{13}}{7}. \] ### Step 7: Compare with the given eccentricity The problem states that the eccentricity is \(\frac{\sqrt{5}}{3}\). We need to check if \(\frac{\sqrt{13}}{7}\) is equal to \(\frac{\sqrt{5}}{3}\): Cross-multiplying gives: \[ \sqrt{13} \cdot 3 \quad \text{and} \quad \sqrt{5} \cdot 7. \] Calculating both sides: - Left side: \(3\sqrt{13}\) - Right side: \(7\sqrt{5}\) Since \(3\sqrt{13} \neq 7\sqrt{5}\), the statement that the eccentricity is \(\frac{\sqrt{5}}{3}\) is false. ### Final Conclusion The eccentricity of the ellipse \(\frac{x^2}{49} + \frac{y^2}{36} = 1\) is \(\frac{\sqrt{13}}{7}\), which is not equal to \(\frac{\sqrt{5}}{3}\). ---
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