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Normal to the circle x^(2)+y^(2)=4 divid...

Normal to the circle `x^(2)+y^(2)=4` divides the circle having centre at (2,4) and radius 2 in the ares of ratio `(pi -2) : (3pi +2)`. Then the normal can be

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To solve the problem step by step, we will follow the reasoning presented in the video transcript. ### Step 1: Understand the Problem We have a circle given by the equation \( x^2 + y^2 = 4 \), which has a center at the origin (0, 0) and a radius of 2. We also have another circle with center (2, 4) and radius 2. A normal to the first circle divides the area of the second circle in the ratio \( \frac{\pi - 2}{3\pi + 2} \). ### Step 2: Write the Equation of the Normal The normal to the circle at any point can be expressed in the form \( y = mx \) where \( m \) is the slope. Since the normal passes through the origin, we can represent it as such. ### Step 3: Find the Area of the Segments The area of the segment cut off by the normal in the second circle can be calculated using the formula for the area of a circular segment. The area \( A \) of a segment is given by: \[ A = \frac{r^2}{2}(\theta - \sin \theta) \] where \( r \) is the radius and \( \theta \) is the angle in radians. ### Step 4: Set Up the Areas Let \( A_1 \) be the area of the segment on one side of the normal and \( A_2 \) be the area on the other side. The given ratio is: \[ \frac{A_1}{A_2} = \frac{\pi - 2}{3\pi + 2} \] Using the area formula, we can express \( A_1 \) and \( A_2 \) in terms of \( \theta \) (the angle subtended by the segment at the center of the second circle). ### Step 5: Calculate Areas The total area of the second circle is: \[ \text{Total Area} = \pi r^2 = \pi \cdot 2^2 = 4\pi \] Thus, we can express \( A_2 \) as: \[ A_2 = 4\pi - A_1 \] ### Step 6: Substitute in the Ratio Substituting \( A_2 \) into the ratio gives: \[ \frac{A_1}{4\pi - A_1} = \frac{\pi - 2}{3\pi + 2} \] Cross-multiplying leads to: \[ A_1(3\pi + 2) = (4\pi - A_1)(\pi - 2) \] ### Step 7: Solve for \( A_1 \) Expanding and simplifying the equation will allow us to find \( A_1 \) in terms of \( \theta \). ### Step 8: Find \( \theta \) After simplifying, we will find that \( \theta \) satisfies the equation: \[ \theta - \sin \theta = \frac{\pi}{2} - 1 \] By inspection or numerical methods, we find that \( \theta = \frac{\pi}{2} \) satisfies this equation. ### Step 9: Calculate the Lengths Using \( \theta = \frac{\pi}{2} \), we can find the lengths involved using the Pythagorean theorem. ### Step 10: Find the Slope \( m \) Using the distance from the center of the second circle (2, 4) to the line \( y = mx \), we set up the equation: \[ \frac{|2m - 4|}{\sqrt{m^2 + 1}} = \sqrt{2} \] Squaring both sides and simplifying will yield a quadratic in \( m \). ### Step 11: Solve the Quadratic The quadratic will yield two possible values for \( m \), which correspond to the slopes of the normals. ### Final Answer The equations of the normals are: \[ y = x \quad \text{and} \quad y = 7x \]

To solve the problem step by step, we will follow the reasoning presented in the video transcript. ### Step 1: Understand the Problem We have a circle given by the equation \( x^2 + y^2 = 4 \), which has a center at the origin (0, 0) and a radius of 2. We also have another circle with center (2, 4) and radius 2. A normal to the first circle divides the area of the second circle in the ratio \( \frac{\pi - 2}{3\pi + 2} \). ### Step 2: Write the Equation of the Normal The normal to the circle at any point can be expressed in the form \( y = mx \) where \( m \) is the slope. Since the normal passes through the origin, we can represent it as such. ...
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CENGAGE ENGLISH-CIRCLE -Multiple Correct Anser Type
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  9. The circles x^2+y^2-2x-4y+1=0 and x^2+y^2+4x+4y-1=0 ............a)touc...

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  12. The equation of a circle of radius 1 touching the circles x^2+y^2-2|x|...

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  13. The center(s) of the circle(s) passing through the points (0, 0) and ...

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  14. Find the equations of straight lines which pass through the intersecti...

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  16. Normal to the circle x^(2)+y^(2)=4 divides the circle having centre at...

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  17. Circle(s) touching x-axis at a distance 3 from the origin and having a...

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  18. A circle S passes through the point (0, 1) and is orthogonal to the ci...

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