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There are two circles C(1) and C(2) touc...

There are two circles `C_(1)` and `C_(2)` touching each other and the coordinate axes, if `C_(1)` is smaller than `C_(2)` and its radius is 2 units, then radius of `C_(2)`, is

A

`6+4sqrt(2)`

B

`2+2sqrt(2)`

C

`3+2sqrt(2)`

D

none of these

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To solve the problem, we need to find the radius of the larger circle \( C_2 \) given that the radius of the smaller circle \( C_1 \) is 2 units. Both circles touch each other and the coordinate axes. ### Step-by-Step Solution: 1. **Understanding the Configuration**: - Let the radius of circle \( C_1 \) be \( r_1 = 2 \) units. - Let the radius of circle \( C_2 \) be \( r_2 \) (which we need to find). - Both circles touch each other and the coordinate axes. 2. **Positioning the Circles**: - Circle \( C_1 \) can be positioned with its center at \( (2, 2) \) since it touches both the x-axis and y-axis. - Circle \( C_2 \) will have its center at \( (r_2, r_2) \) since it also touches both axes. 3. **Distance Between the Centers**: - The distance between the centers of the two circles \( C_1 \) and \( C_2 \) can be calculated using the distance formula: \[ \text{Distance} = \sqrt{(r_2 - 2)^2 + (r_2 - 2)^2} = \sqrt{2(r_2 - 2)^2} = \sqrt{2} |r_2 - 2| \] 4. **Condition for Touching Circles**: - For the circles to touch each other, the distance between their centers must equal the sum of their radii: \[ \sqrt{2} |r_2 - 2| = r_1 + r_2 = 2 + r_2 \] - This simplifies to: \[ \sqrt{2} |r_2 - 2| = 2 + r_2 \] 5. **Solving the Equation**: - We can consider two cases for \( |r_2 - 2| \): - Case 1: \( r_2 - 2 \geq 0 \) (i.e., \( r_2 \geq 2 \)): \[ \sqrt{2}(r_2 - 2) = 2 + r_2 \] \[ \sqrt{2}r_2 - 2\sqrt{2} = 2 + r_2 \] \[ (\sqrt{2} - 1)r_2 = 2 + 2\sqrt{2} \] \[ r_2 = \frac{2 + 2\sqrt{2}}{\sqrt{2} - 1} \] - Case 2: \( r_2 - 2 < 0 \) (i.e., \( r_2 < 2 \)): \[ \sqrt{2}(2 - r_2) = 2 + r_2 \] \[ 2\sqrt{2} - \sqrt{2}r_2 = 2 + r_2 \] \[ (1 + \sqrt{2})r_2 = 2\sqrt{2} - 2 \] \[ r_2 = \frac{2(\sqrt{2} - 1)}{1 + \sqrt{2}} \] 6. **Calculating the Radius**: - We will only consider the first case since \( C_2 \) is larger than \( C_1 \): \[ r_2 = \frac{2 + 2\sqrt{2}}{\sqrt{2} - 1} \] - Rationalizing the denominator: \[ r_2 = \frac{(2 + 2\sqrt{2})(\sqrt{2} + 1)}{(\sqrt{2} - 1)(\sqrt{2} + 1)} = \frac{(2\sqrt{2} + 2 + 4 + 2\sqrt{2})}{2 - 1} = 6 + 4\sqrt{2} \] ### Final Answer: The radius of circle \( C_2 \) is \( 6 + 4\sqrt{2} \) units. ---

To solve the problem, we need to find the radius of the larger circle \( C_2 \) given that the radius of the smaller circle \( C_1 \) is 2 units. Both circles touch each other and the coordinate axes. ### Step-by-Step Solution: 1. **Understanding the Configuration**: - Let the radius of circle \( C_1 \) be \( r_1 = 2 \) units. - Let the radius of circle \( C_2 \) be \( r_2 \) (which we need to find). - Both circles touch each other and the coordinate axes. ...
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OBJECTIVE RD SHARMA ENGLISH-CIRCLES-Chapter Test
  1. There are two circles C(1) and C(2) touching each other and the coordi...

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  2. The two circles x^2 + y^2 -2x+6y+6=0 and x^2 + y^2 - 5x + 6y + 15 = 0 ...

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  3. The two circles x^(2)+y^(2)-2x-2y-7=0 and 3(x^(2)+y^(2))-8x+29y=0

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  4. The centre of a circle passing through (0,0), (1,0) and touching the C...

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  5. The circle x^2+y^2=4 cuts the circle x^2+y^2+2x+3y-5=0 in A and B, The...

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  6. One of the limit point of the coaxial system of circles containing x^(...

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  7. A circle touches y-axis at (0, 2) and has an intercept of 4 units on t...

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  8. The equation of the circle whose one diameter is PQ, where the ordinat...

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  9. The circle x^(2)+y^(2)+4x-7y+12=0 cuts an intercept on Y-axis is of le...

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  10. Prove that the equation of any tangent to the circle x^2+y^2-2x+4y-4=0...

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  11. The angle between the pair of tangents from the point (1, 1/2) to the...

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  12. The intercept on the line y=x by the circle x^(2)+y^(2)-2x=0 is AB. Eq...

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  13. If 3x+y=0 is a tangent to a circle whose center is (2,-1) , then find ...

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  14. The locus of the midpoint of a chord of the circle x^2+y^2=4 which sub...

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  15. Two tangents to the circle x^(2) +y^(2) = 4 at the points A and B meet...

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  16. A tangent is drawn to the circle 2(x^(2)+y^(2))-3x+4y=0 and it touch...

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  17. the length of the chord of the circle x^(2)+y^(2)=25 passing through ...

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  18. If the points A(2, 5) and B are symmetrical about the tangent to the c...

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  19. The equation of the circle of radius 2 sqrt(2) whose centre lies on th...

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  20. Prove that the maximum number of points with rational coordinates on a...

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  21. The equation of a circle C is x^(2)+y^(2)-6x-8y-11=0. The number of re...

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