Consider the curve given by the equation 3x2+y4+6x=253. It can be shown that dxdy=4y3−6(x+1).Write the equation of the horizontal line that is tangent to the curve and is above the x-axis.
Q. Consider the curve given by the equation 3x2+y4+6x=253. It can be shown that dxdy=4y3−6(x+1).Write the equation of the horizontal line that is tangent to the curve and is above the x-axis.
Find Tangent Point: To find the equation of a horizontal line that is tangent to the curve, we need to find a point on the curve where the derivative dxdy is equal to 0, because the slope of a horizontal line is 0.
Derivative Calculation: The derivative dxdy is given as 4y3−6(x+1). For a horizontal tangent line, dxdy must be equal to 0. Therefore, we set the numerator of the derivative equal to zero to find the x-value of the point of tangency.−6(x+1)=0
Solve for x: Solving for x, we get:−6(x+1)=0−6x−6=0−6x=6x=−1
Find y-Value: Now that we have the x-value, we need to find the corresponding y-value(s) on the curve. We substitute x=−1 into the original equation of the curve to find y.3(−1)2+y4+6(−1)=253
Simplify Equation: Simplifying the equation, we get:3(1)+y4−6=2533+y4−6=253y4=253+6−3y4=256
Solve for y: Taking the fourth root of both sides to solve for y, we get:y=±4Since we are looking for the horizontal tangent line above the x-axis, we only consider the positive y-value.y=4
Equation of Tangent Line: We now have the point of tangency (−1,4). The equation of a horizontal line is of the form y=k, where k is the y-coordinate of the point through which the line passes.Therefore, the equation of the horizontal line tangent to the curve and above the x-axis is y=4.
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