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The eccentricity of the ellipse, which p...

The eccentricity of the ellipse, which passes through the points (2, −2) and (−3,1) is :

A

`(1)/(sqrt(5))`

B

`sqrt((2)/(5))`

C

`sqrt((3)/(5))`

D

`sqrt((4)/(5))`

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To find the eccentricity of the ellipse that passes through the points (2, -2) and (-3, 1), we can follow these steps: ### Step 1: Write the standard equation of the ellipse The standard form of the ellipse is given by: \[ \frac{x^2}{a^2} + \frac{y^2}{b^2} = 1 \] where \(a\) is the semi-major axis, \(b\) is the semi-minor axis, and the eccentricity \(e\) is defined as: \[ e = \frac{c}{a} \] with \(c^2 = a^2 - b^2\). ### Step 2: Substitute the first point (2, -2) into the ellipse equation Substituting the coordinates of the first point (2, -2): \[ \frac{(2)^2}{a^2} + \frac{(-2)^2}{b^2} = 1 \] This simplifies to: \[ \frac{4}{a^2} + \frac{4}{b^2} = 1 \quad \text{(Equation 1)} \] ### Step 3: Substitute the second point (-3, 1) into the ellipse equation Now, substituting the coordinates of the second point (-3, 1): \[ \frac{(-3)^2}{a^2} + \frac{(1)^2}{b^2} = 1 \] This simplifies to: \[ \frac{9}{a^2} + \frac{1}{b^2} = 1 \quad \text{(Equation 2)} \] ### Step 4: Solve the system of equations Now we have two equations: 1. \(\frac{4}{a^2} + \frac{4}{b^2} = 1\) 2. \(\frac{9}{a^2} + \frac{1}{b^2} = 1\) From Equation 1, we can express \(\frac{4}{b^2}\) in terms of \(\frac{4}{a^2}\): \[ \frac{4}{b^2} = 1 - \frac{4}{a^2} \quad \Rightarrow \quad \frac{1}{b^2} = \frac{1}{4} - \frac{1}{a^2} \] Substituting this into Equation 2: \[ \frac{9}{a^2} + \left(\frac{1}{4} - \frac{1}{a^2}\right) = 1 \] This simplifies to: \[ \frac{8}{a^2} + \frac{1}{4} = 1 \] Multiplying through by \(4a^2\) gives: \[ 32 + a^2 = 4a^2 \quad \Rightarrow \quad 3a^2 = 32 \quad \Rightarrow \quad a^2 = \frac{32}{3} \] ### Step 5: Find \(b^2\) Substituting \(a^2\) back into Equation 1 to find \(b^2\): \[ \frac{4}{\frac{32}{3}} + \frac{4}{b^2} = 1 \quad \Rightarrow \quad \frac{12}{32} + \frac{4}{b^2} = 1 \] This simplifies to: \[ \frac{3}{8} + \frac{4}{b^2} = 1 \quad \Rightarrow \quad \frac{4}{b^2} = \frac{5}{8} \quad \Rightarrow \quad b^2 = \frac{32}{5} \] ### Step 6: Calculate the eccentricity Now we can find \(c^2\): \[ c^2 = a^2 - b^2 = \frac{32}{3} - \frac{32}{5} \] Finding a common denominator (15): \[ c^2 = \frac{160}{15} - \frac{96}{15} = \frac{64}{15} \] Now, we can find the eccentricity: \[ e = \frac{c}{a} = \sqrt{\frac{64}{15}} \div \sqrt{\frac{32}{3}} = \sqrt{\frac{64}{15} \cdot \frac{3}{32}} = \sqrt{\frac{192}{480}} = \sqrt{\frac{2}{5}} \] ### Final Answer Thus, the eccentricity of the ellipse is: \[ e = \sqrt{\frac{2}{5}} \] ---

To find the eccentricity of the ellipse that passes through the points (2, -2) and (-3, 1), we can follow these steps: ### Step 1: Write the standard equation of the ellipse The standard form of the ellipse is given by: \[ \frac{x^2}{a^2} + \frac{y^2}{b^2} = 1 \] where \(a\) is the semi-major axis, \(b\) is the semi-minor axis, and the eccentricity \(e\) is defined as: ...
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