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if r(1) and r(2) are distances of points...

if `r_(1)` and `r_(2)` are distances of points on the ellipse `5x^(2)+5y^(2)+6xy-8=0` which are at maximum and minimum distance from the origin then

A

`r_(1)+r_(2)=3`

B

`|r_(1)-r_(2)|=1`

C

`|r_(1)-2r_(2)|=0`

D

`r_(1)+2r_(2)=4`

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To solve the problem of finding the maximum and minimum distances from the origin to the ellipse given by the equation \(5x^2 + 5y^2 + 6xy - 8 = 0\), we can follow these steps: ### Step 1: Rewrite the ellipse equation We start with the equation of the ellipse: \[ 5x^2 + 5y^2 + 6xy - 8 = 0 \] We can express \(x\) and \(y\) in terms of polar coordinates, where \(x = r \cos \theta\) and \(y = r \sin \theta\). ### Step 2: Substitute polar coordinates into the ellipse equation Substituting \(x\) and \(y\) into the ellipse equation gives: \[ 5(r \cos \theta)^2 + 5(r \sin \theta)^2 + 6(r \cos \theta)(r \sin \theta) - 8 = 0 \] This simplifies to: \[ 5r^2 \cos^2 \theta + 5r^2 \sin^2 \theta + 6r^2 \cos \theta \sin \theta - 8 = 0 \] ### Step 3: Simplify the equation Using the identity \(\cos^2 \theta + \sin^2 \theta = 1\), we can simplify the equation: \[ 5r^2 + 6r^2 \cos \theta \sin \theta - 8 = 0 \] This can be rewritten as: \[ 5r^2 + 3r^2 \sin(2\theta) - 8 = 0 \] ### Step 4: Rearrange to find \(r^2\) Rearranging gives: \[ 5r^2 + 3r^2 \sin(2\theta) = 8 \] Factoring out \(r^2\): \[ r^2(5 + 3 \sin(2\theta)) = 8 \] Thus, we have: \[ r^2 = \frac{8}{5 + 3 \sin(2\theta)} \] ### Step 5: Find maximum and minimum values of \(r\) To find the maximum and minimum distances, we need to analyze the expression \(\frac{8}{5 + 3 \sin(2\theta)}\). The maximum value of \(r^2\) occurs when \(5 + 3 \sin(2\theta)\) is minimized, and the minimum value occurs when \(5 + 3 \sin(2\theta)\) is maximized. - The maximum value of \(\sin(2\theta)\) is \(1\): \[ 5 + 3 \cdot 1 = 8 \quad \Rightarrow \quad r^2_{\text{min}} = \frac{8}{8} = 1 \quad \Rightarrow \quad r_{\text{min}} = 1 \] - The minimum value of \(\sin(2\theta)\) is \(-1\): \[ 5 + 3 \cdot (-1) = 2 \quad \Rightarrow \quad r^2_{\text{max}} = \frac{8}{2} = 4 \quad \Rightarrow \quad r_{\text{max}} = 2 \] ### Step 6: Conclusion The maximum distance \(r_1\) from the origin is \(2\) and the minimum distance \(r_2\) is \(1\). Thus, the final answer is: \[ r_1 = 2, \quad r_2 = 1 \]

To solve the problem of finding the maximum and minimum distances from the origin to the ellipse given by the equation \(5x^2 + 5y^2 + 6xy - 8 = 0\), we can follow these steps: ### Step 1: Rewrite the ellipse equation We start with the equation of the ellipse: \[ 5x^2 + 5y^2 + 6xy - 8 = 0 \] We can express \(x\) and \(y\) in terms of polar coordinates, where \(x = r \cos \theta\) and \(y = r \sin \theta\). ...
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