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STATEMENT-1 : Equation of circle which t...

STATEMENT-1 : Equation of circle which touches the circle `x^(2) + y^(2) - 6x +6y + 17 = 0` externally and to which the lines `x^(2) - 3xy - 3x + 9y = 0` are normal is `x^(2) + y^(2) - 6x - 2y +1 = 0`.
STATEMENT-2 : Equation of circle which touches the circle `x^(2) + y^(2) -6x + 6y + 17 = 0` internally and to which the line `x^(2) - 3xy - 3x + 9y = 0` are normal is `x^(2) + y^(2) -6x - 2y -15 = 0`.
STATMENT-3 : Equation of circle which is orthogonal to circle `x^(2) + y^(2) -6x + 6y + 17 = 0` and have normals along `x^(2) -3xy -3x + 9y =0` is `x^(2) + y^(2) - 6x -2 y-5 = 0`.

A

T T F

B

T F F

C

F F F

D

T T T

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to analyze each statement regarding the circles and their properties. Let's break down the solution step by step. ### Step 1: Analyze Statement 1 We have the first circle given by the equation: \[ x^2 + y^2 - 6x + 6y + 17 = 0 \] **Finding the center and radius of the first circle:** 1. Rewrite the equation in standard form: \[ (x^2 - 6x) + (y^2 + 6y) + 17 = 0 \] Completing the square: \[ (x - 3)^2 - 9 + (y + 3)^2 - 9 + 17 = 0 \] \[ (x - 3)^2 + (y + 3)^2 - 1 = 0 \] Thus, the center is \( C_1(3, -3) \) and the radius \( r_1 = 1 \). **Finding the equation of the second circle:** 2. The second circle touches the first circle externally. Let the center of the second circle be \( C_2(a, b) \) and its radius be \( r_2 \). The condition for external tangency is: \[ |C_1C_2| = r_1 + r_2 \] The distance \( |C_1C_2| \) is given by: \[ \sqrt{(a - 3)^2 + (b + 3)^2} \] 3. The lines given by: \[ x^2 - 3xy - 3x + 9y = 0 \] can be factored to find the slopes of the normals. Solving gives us the points where the normals intersect. 4. The equation of the second circle is given as: \[ x^2 + y^2 - 6x - 2y + 1 = 0 \] This can be rewritten to find its center and radius: \[ (x - 3)^2 + (y - 1)^2 = 1 \] Thus, the center is \( C_2(3, 1) \) and radius \( r_2 = 1 \). 5. Check the distance condition: \[ |C_1C_2| = \sqrt{(3 - 3)^2 + (1 + 3)^2} = \sqrt{16} = 4 \] The sum of the radii: \[ r_1 + r_2 = 1 + 1 = 2 \] Since \( 4 \neq 2 \), Statement 1 is **incorrect**. ### Step 2: Analyze Statement 2 For the second statement, we need to find a circle that touches the first circle internally. 1. The condition for internal tangency is: \[ |C_1C_2| = |r_1 - r_2| \] Using the same centers and radius as before, we find: \[ |C_1C_2| = 4 \] Setting up the equation: \[ 4 = |1 - r_2| \] This gives two cases: - \( 1 - r_2 = 4 \) → \( r_2 = -3 \) (not possible) - \( r_2 - 1 = 4 \) → \( r_2 = 5 \) 2. The equation of the circle is: \[ (x - 3)^2 + (y - 1)^2 = 25 \] This simplifies to: \[ x^2 + y^2 - 6x - 2y - 15 = 0 \] This matches the given equation for Statement 2, so it is **correct**. ### Step 3: Analyze Statement 3 For the third statement, we need to find a circle orthogonal to the first circle. 1. The condition for orthogonality is: \[ |C_1C_2|^2 = r_1^2 + r_2^2 \] We already know: \[ |C_1C_2| = 4 \quad \text{and} \quad r_1 = 1 \] Thus: \[ 16 = 1 + r_2^2 \quad \Rightarrow \quad r_2^2 = 15 \quad \Rightarrow \quad r_2 = \sqrt{15} \] 2. The equation of the circle becomes: \[ (x - 3)^2 + (y - 1)^2 = 15 \] This simplifies to: \[ x^2 + y^2 - 6x - 2y - 5 = 0 \] This matches the given equation for Statement 3, so it is also **correct**. ### Conclusion - Statement 1: **Incorrect** - Statement 2: **Correct** - Statement 3: **Correct**
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