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Statement:1 There is only one circle whi...

Statement:1 There is only one circle which touches the curve `xy =1 at (1,1)` and x-axis. Because
Statement 2: Any circle touching the hypebola `xy=1 at (1,1) ` can be written in the from `(x-1)^(2) + (y-1) ^(2) + lamda( y+x-2) =0.`

A

Stateme-1 is True, Statement-2 is True, Statemetn-2 is correct explanation for Statement-1

B

Statement-1 is True, Statement-2 is True, Statement-2 is NOT a correct explanation for Statement-1

C

Statement-1 is True, Statement-2 is False

D

Statement-1 is False, Statement-2 is ture

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to analyze the two statements provided and derive the necessary equations step by step. ### Step 1: Understand the Problem We have two statements: 1. There is only one circle which touches the curve \(xy = 1\) at the point \((1, 1)\) and the x-axis. 2. Any circle touching the hyperbola \(xy = 1\) at \((1, 1)\) can be written in the form \((x-1)^2 + (y-1)^2 + \lambda(y+x-2) = 0\). ### Step 2: Find the Equation of the Tangent to the Hyperbola The hyperbola is given by \(xy = 1\). To find the tangent at the point \((1, 1)\): - The slope of the hyperbola at \((1, 1)\) can be found using implicit differentiation: \[ \frac{dy}{dx} = -\frac{y}{x^2} \] At \((1, 1)\), this gives: \[ \frac{dy}{dx} = -1 \] - The equation of the tangent line at \((1, 1)\) is: \[ y - 1 = -1(x - 1) \implies y + x - 2 = 0 \] ### Step 3: Write the General Equation of the Circle The general equation of a circle that touches the tangent line can be expressed as: \[ (x - 1)^2 + (y - 1)^2 + \lambda(y + x - 2) = 0 \] Expanding this, we get: \[ x^2 - 2x + 1 + y^2 - 2y + 1 + \lambda(y + x - 2) = 0 \] This simplifies to: \[ x^2 + y^2 + (\lambda - 2)x + (\lambda - 2)y + 2 = 0 \] ### Step 4: Determine Conditions for the Circle to Touch the x-axis For the circle to touch the x-axis, the distance from the center of the circle to the x-axis must equal the radius. The center of the circle is at \((1, 1)\) with respect to the equation we derived. The radius \(r\) can be expressed as: \[ r = \sqrt{g^2 + f^2 - c} \] where \(g = \frac{\lambda - 2}{2}\), \(f = \frac{\lambda - 2}{2}\), and \(c = -2\). ### Step 5: Set Up the Equation for Touching the x-axis The condition for touching the x-axis is: \[ \text{y-coordinate of center} = \text{radius} \] Thus: \[ \frac{\lambda - 2}{2} = \sqrt{\left(\frac{\lambda - 2}{2}\right)^2 + \left(\frac{\lambda - 2}{2}\right)^2 + 2} \] ### Step 6: Solve for \(\lambda\) Squaring both sides and simplifying will yield a quadratic equation in \(\lambda\): \[ \lambda^2 - 4\lambda + 4 = 0 \] This has two solutions, indicating that there are two circles that can touch the hyperbola at the point \((1, 1)\) and the x-axis. ### Conclusion - **Statement 1** is incorrect because there are two circles, not one. - **Statement 2** is correct as it correctly describes the form of the circles. ### Final Answer - Statement 1: False - Statement 2: True
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