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If the straight line 4ax+3by=24 is a no...

If the straight line `4ax+3by=24` is a normal to the ellipse `(x^(2))/(a^(2))+(y^(2))/(b^(2))=1 (agtb)`, then find the the coordinates of focii and the ellipse

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To solve the problem, we need to find the coordinates of the foci of the ellipse given that the line \(4ax + 3by = 24\) is a normal to the ellipse defined by \(\frac{x^2}{a^2} + \frac{y^2}{b^2} = 1\) where \(a > b\). ### Step 1: Write down the given normal equation The equation of the normal line is given as: \[ 4ax + 3by = 24 \] Let's label this as Equation (1). ### Step 2: Identify the general point on the ellipse A general point on the ellipse can be represented as: \[ P(a \cos \theta, b \sin \theta) \] where \(\theta\) is a parameter. ### Step 3: Write down the general equation of the normal to the ellipse The general equation of the normal to the ellipse at point \(P(x_1, y_1)\) is given by: \[ \frac{a^2 x}{x_1} - \frac{b^2 y}{y_1} = a^2 - b^2 \] Substituting \(x_1 = a \cos \theta\) and \(y_1 = b \sin \theta\), we have: \[ \frac{a^2 x}{a \cos \theta} - \frac{b^2 y}{b \sin \theta} = a^2 - b^2 \] This simplifies to: \[ \frac{a x}{\cos \theta} - \frac{b y}{\sin \theta} = a^2 - b^2 \] Let's label this as Equation (2). ### Step 4: Equate the two equations Since the line \(4ax + 3by = 24\) is a normal to the ellipse, Equations (1) and (2) must be identical. Therefore, we can equate the coefficients of \(x\), \(y\), and the constant terms. From Equation (1): - Coefficient of \(x\) is \(4a\) - Coefficient of \(y\) is \(3b\) - Constant term is \(24\) From Equation (2): - Coefficient of \(x\) is \(\frac{a}{\cos \theta}\) - Coefficient of \(y\) is \(-\frac{b}{\sin \theta}\) - Constant term is \(a^2 - b^2\) ### Step 5: Set up the equations From the coefficients, we have: 1. \(\frac{a}{\cos \theta} = 4a\) 2. \(-\frac{b}{\sin \theta} = 3b\) 3. \(a^2 - b^2 = 24\) ### Step 6: Solve for \(\theta\) From the first equation: \[ \cos \theta = \frac{1}{4} \] From the second equation: \[ \sin \theta = -\frac{1}{3} \] ### Step 7: Use Pythagorean identity We know that: \[ \cos^2 \theta + \sin^2 \theta = 1 \] Substituting the values: \[ \left(\frac{1}{4}\right)^2 + \left(-\frac{1}{3}\right)^2 = 1 \] Calculating: \[ \frac{1}{16} + \frac{1}{9} = \frac{9}{144} + \frac{16}{144} = \frac{25}{144} \neq 1 \] This indicates that we need to check our values for \(\theta\). ### Step 8: Find \(a^2 - b^2\) From the third equation: \[ a^2 - b^2 = 24 \] ### Step 9: Use the relationship between \(a\) and \(b\) Since \(a > b\), we can express \(b^2\) in terms of \(a^2\): \[ b^2 = a^2 - 24 \] ### Step 10: Find the coordinates of the foci The foci of the ellipse are given by the formula: \[ (\pm ae, 0) \] where \(e = \sqrt{1 - \frac{b^2}{a^2}}\). Substituting \(b^2 = a^2 - 24\): \[ e = \sqrt{1 - \frac{a^2 - 24}{a^2}} = \sqrt{\frac{24}{a^2}} \] Thus, the coordinates of the foci are: \[ \left(\pm a \sqrt{\frac{24}{a^2}}, 0\right) = \left(\pm \sqrt{24}, 0\right) = \left(\pm 2\sqrt{6}, 0\right) \] ### Final Answer The coordinates of the foci of the ellipse are: \[ (2\sqrt{6}, 0) \text{ and } (-2\sqrt{6}, 0) \]

To solve the problem, we need to find the coordinates of the foci of the ellipse given that the line \(4ax + 3by = 24\) is a normal to the ellipse defined by \(\frac{x^2}{a^2} + \frac{y^2}{b^2} = 1\) where \(a > b\). ### Step 1: Write down the given normal equation The equation of the normal line is given as: \[ 4ax + 3by = 24 \] Let's label this as Equation (1). ...
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