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Let e and l are the eccentricity and len...

Let e and l are the eccentricity and length of the lactus rectum respectively of the conic described parametrically by `x=t^(2)-t+1, y=t^(2)-t+1`, then the value of `(e )/(l^(2))` is equal to

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To solve the problem, we need to analyze the parametric equations given and identify the conic section they represent. The equations are: \[ x = t^2 - t + 1 \] \[ y = t^2 - t + 1 \] ### Step 1: Combine the equations First, we can combine the two equations to find a relationship between \(x\) and \(y\). Adding the two equations: \[ x + y = (t^2 - t + 1) + (t^2 - t + 1) = 2t^2 - 2t + 2 \] This simplifies to: \[ x + y = 2(t^2 - t + 1) = 2t^2 - 2t + 2 \] ### Step 2: Subtract the equations Now, let's subtract the second equation from the first: \[ x - y = (t^2 - t + 1) - (t^2 - t + 1) = 0 \] This means: \[ x - y = 0 \implies x = y \] ### Step 3: Express \(t\) in terms of \(x\) and \(y\) From the equation \(x + y = 2(t^2 - t + 1)\), we can express \(t\) in terms of \(x\) and \(y\): \[ x + y = 2t^2 - 2t + 2 \implies t^2 - t + 1 = \frac{x + y}{2} \] ### Step 4: Substitute \(t\) back Next, we can express \(t\) from \(x - y\): \[ t = \frac{x - y}{2} \] ### Step 5: Identify the conic section Now we can substitute \(t\) back into the equations to find the relationship between \(x\) and \(y\). However, since we already know \(x = y\), we can conclude that the conic section is a parabola. ### Step 6: Find the eccentricity and length of the latus rectum For a parabola, the eccentricity \(e = 1\) and the length of the latus rectum \(l = 4a\). To find \(a\), we need to identify the vertex of the parabola. The vertex occurs at the minimum point of the quadratic \(t^2 - t + 1\). Completing the square or using the vertex formula gives us \(a = 1\). Thus, the length of the latus rectum is: \[ l = 4a = 4 \cdot 1 = 4 \] ### Step 7: Calculate \(\frac{e}{l^2}\) Now we can calculate the required value: \[ \frac{e}{l^2} = \frac{1}{4^2} = \frac{1}{16} \] ### Final Answer The value of \(\frac{e}{l^2}\) is: \[ \frac{1}{16} \]
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