Answer is: option2
\( y = \frac{3}{2}x - \frac{1}{2} \)Solution:
Find the equation of the line normal to the graph of \( 2x^2 + 3y^2 = 5 \) at the point \( (1,1) \).
Steps:
1. Implicit Differentiation:
Differentiate the equation \( 2x^2 + 3y^2 = 5 \) with respect to \( x \):
\[ 4x + 6y \frac{dy}{dx} = 0 \]2. Solve for \( \frac{dy}{dx} \):
\[ 6y \frac{dy}{dx} = -4x \] \[ \frac{dy}{dx} = \frac{-4x}{6y} = \frac{-2x}{3y} \]3. Substitute the Point \( (1, 1) \):
Substitute \( x = 1 \) and \( y = 1 \) into the equation for \( \frac{dy}{dx} \):
\[ \frac{dy}{dx} = \frac{-2(1)}{3(1)} = \frac{-2}{3} \]So, the slope of the tangent line at \( (1, 1) \) is \( \frac{-2}{3} \).
4. Find the Slope of the Normal Line:
The slope of the normal line is the negative reciprocal of the slope of the tangent line. Therefore, the slope of the normal line is:
\[ \text{slope of normal} = \frac{3}{2} \]5. Equation of the Normal Line:
The equation of the line is in point-slope form:
\[ y - y_1 = m(x - x_1) \]Substituting the slope \( m = \frac{3}{2} \) and the point \( (1, 1) \):
\[ y - 1 = \frac{3}{2}(x - 1) \]Expanding this:
\[ y - 1 = \frac{3}{2}x - \frac{3}{2} \] \[ y = \frac{3}{2}x - \frac{3}{2} + 1 \] \[ y = \frac{3}{2}x - \frac{1}{2} \]Final Answer:
The equation of the line normal to the graph at \( (1, 1) \) is:
\[ y = \frac{3}{2}x - \frac{1}{2} \]The correct answer is (B).