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A point which is inside the circle x^(2)...

A point which is inside the circle `x^(2)+y^(2)+3x-3y+2=0` is :

A

(-1, 3)

B

(-2, 1)

C

(2, 1)

D

None of these

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The correct Answer is:
To determine if a point is inside the circle defined by the equation \(x^2 + y^2 + 3x - 3y + 2 = 0\), we will follow these steps: ### Step 1: Rewrite the Circle's Equation We start with the equation of the circle: \[ x^2 + y^2 + 3x - 3y + 2 = 0 \] We can rearrange this into the standard form of a circle by completing the square. ### Step 2: Complete the Square 1. For \(x^2 + 3x\): - Take half of the coefficient of \(x\) (which is \(\frac{3}{2}\)), square it to get \(\left(\frac{3}{2}\right)^2 = \frac{9}{4}\). - Rewrite: \[ x^2 + 3x = \left(x + \frac{3}{2}\right)^2 - \frac{9}{4} \] 2. For \(y^2 - 3y\): - Take half of the coefficient of \(y\) (which is \(-\frac{3}{2}\)), square it to get \(\left(-\frac{3}{2}\right)^2 = \frac{9}{4}\). - Rewrite: \[ y^2 - 3y = \left(y - \frac{3}{2}\right)^2 - \frac{9}{4} \] ### Step 3: Substitute Back into the Equation Substituting these back into the original equation gives: \[ \left(x + \frac{3}{2}\right)^2 - \frac{9}{4} + \left(y - \frac{3}{2}\right)^2 - \frac{9}{4} + 2 = 0 \] Simplifying this: \[ \left(x + \frac{3}{2}\right)^2 + \left(y - \frac{3}{2}\right)^2 - \frac{9}{2} + 2 = 0 \] \[ \left(x + \frac{3}{2}\right)^2 + \left(y - \frac{3}{2}\right)^2 = \frac{5}{2} \] ### Step 4: Identify the Center and Radius From the equation \(\left(x + \frac{3}{2}\right)^2 + \left(y - \frac{3}{2}\right)^2 = \frac{5}{2}\): - The center of the circle is \((- \frac{3}{2}, \frac{3}{2})\). - The radius \(r\) is \(\sqrt{\frac{5}{2}}\). ### Step 5: Check Points for Inside the Circle To check if a point \((x_1, y_1)\) is inside the circle, we calculate the distance from the center to the point and compare it to the radius. #### Example Point A: \((-1, 3)\) 1. Calculate the distance \(OA\): \[ OA = \sqrt{\left(-1 + \frac{3}{2}\right)^2 + \left(3 - \frac{3}{2}\right)^2} \] \[ = \sqrt{\left(\frac{1}{2}\right)^2 + \left(\frac{3}{2}\right)^2} = \sqrt{\frac{1}{4} + \frac{9}{4}} = \sqrt{\frac{10}{4}} = \sqrt{\frac{5}{2}} \] Since \(OA = r\), point A lies on the circle. #### Example Point B: \((-2, 1)\) 1. Calculate the distance \(OB\): \[ OB = \sqrt{\left(-2 + \frac{3}{2}\right)^2 + \left(1 - \frac{3}{2}\right)^2} \] \[ = \sqrt{\left(-\frac{1}{2}\right)^2 + \left(-\frac{1}{2}\right)^2} = \sqrt{\frac{1}{4} + \frac{1}{4}} = \sqrt{\frac{2}{4}} = \sqrt{\frac{1}{2}} \] Since \(OB < r\), point B lies inside the circle. ### Conclusion The point \((-2, 1)\) is inside the circle.

To determine if a point is inside the circle defined by the equation \(x^2 + y^2 + 3x - 3y + 2 = 0\), we will follow these steps: ### Step 1: Rewrite the Circle's Equation We start with the equation of the circle: \[ x^2 + y^2 + 3x - 3y + 2 = 0 \] We can rearrange this into the standard form of a circle by completing the square. ...
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