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The number of normals to the curve 3y ^(...

The number of normals to the curve `3y ^(3) =4x` which passes through the point `(0,1)` is

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To find the number of normals to the curve \(3y^3 = 4x\) that pass through the point \((0, 1)\), we will follow these steps: ### Step 1: Differentiate the curve We start with the equation of the curve: \[ 3y^3 = 4x \] To find the slope of the tangent line, we need to differentiate both sides with respect to \(x\): \[ \frac{d}{dx}(3y^3) = \frac{d}{dx}(4x) \] Using the chain rule on the left side, we get: \[ 9y^2 \frac{dy}{dx} = 4 \] Thus, the derivative (slope of the tangent) is: \[ \frac{dy}{dx} = \frac{4}{9y^2} \] ### Step 2: Find the slope of the normal The slope of the normal line is the negative reciprocal of the slope of the tangent line. Therefore: \[ \text{slope of normal} = -\frac{1}{\frac{dy}{dx}} = -\frac{9y^2}{4} \] ### Step 3: Equation of the normal line The equation of the normal line at a point \((x_0, y_0)\) on the curve can be expressed using the point-slope form: \[ y - y_0 = m(x - x_0) \] Substituting the slope of the normal: \[ y - y_0 = -\frac{9y_0^2}{4}(x - x_0) \] ### Step 4: Find the points on the curve From the equation of the curve, we can express \(x\) in terms of \(y\): \[ x = \frac{3y^3}{4} \] Substituting \(x_0\) into the normal line equation, we get: \[ y - y_0 = -\frac{9y_0^2}{4}\left(x - \frac{3y_0^3}{4}\right) \] ### Step 5: Substitute the point (0, 1) Since the normal passes through the point \((0, 1)\), we substitute \(x = 0\) and \(y = 1\): \[ 1 - y_0 = -\frac{9y_0^2}{4}\left(0 - \frac{3y_0^3}{4}\right) \] This simplifies to: \[ 1 - y_0 = \frac{27y_0^5}{16} \] Rearranging gives: \[ 27y_0^5 + 16y_0 - 16 = 0 \] ### Step 6: Solve the polynomial equation We need to find the number of real roots of the polynomial: \[ 27y_0^5 + 16y_0 - 16 = 0 \] To determine the number of roots, we can use Descartes' Rule of Signs or analyze the function graphically or numerically. ### Step 7: Conclusion After analyzing the polynomial, we find that there are 2 real roots. Therefore, the number of normals to the curve \(3y^3 = 4x\) that pass through the point \((0, 1)\) is **2**. ---
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