Consider the curve given by the equation y3−8y2+16y−x2+2x=0. It can be shown that dxdy=(3y−4)(y−4)2(x−1). Find the y-coordinate of the point where the line tangent to the curve is the y-axis.y=
Q. Consider the curve given by the equation y3−8y2+16y−x2+2x=0. It can be shown that dxdy=(3y−4)(y−4)2(x−1). Find the y-coordinate of the point where the line tangent to the curve is the y-axis.y=
Find Tangent Point: To find the y-coordinate of the point where the line tangent to the curve is the y-axis, we need to find the point where the derivative (dxdy) is undefined or zero, since the slope of the tangent line to the y-axis is vertical (undefined slope).
Derivative Calculation: The derivative of y with respect to x is given by dxdy=(3y−4)(y−4)2(x−1). For the tangent to be the y-axis, the numerator of the derivative must be zero, because a zero numerator over a non-zero denominator gives a slope of zero, which corresponds to a horizontal line, not a vertical one. Therefore, we need to find where the denominator is zero, which would make the slope undefined.
Solve for Undefined Slope: Set the denominator of the derivative equal to zero to find the y-coordinate where the slope is undefined: (3y−4)(y−4)=0.
Check Y-Values: Solve the equation (3y−4)(y−4)=0 by setting each factor equal to zero: 3y−4=0 or y−4=0.
Factor Out Equation: We need to check which of these y-values, if any, correspond to the point where the tangent is the y-axis. We know that at the y-axis, x=0. So we substitute x=0 into the original equation to see if either of these y-values satisfy the equation.
Final Y-Coordinate: Substitute x=0 into the original equation y3−8y2+16y−x2+2x=0 to get y3−8y2+16y=0.
Final Y-Coordinate: Substitute x=0 into the original equation y3−8y2+16y−x2+2x=0 to get y3−8y2+16y=0.Factor out y from the equation y3−8y2+16y=0 to get y(y2−8y+16)=0.
Final Y-Coordinate: Substitute x=0 into the original equation y3−8y2+16y−x2+2x=0 to get y3−8y2+16y=0.Factor out y from the equation y3−8y2+16y=0 to get y(y2−8y+16)=0.The factored form of y2−8y+16 is (y−4)2, so the equation becomes y(y−4)2=0.
Final Y-Coordinate: Substitute x=0 into the original equation y3−8y2+16y−x2+2x=0 to get y3−8y2+16y=0.Factor out y from the equation y3−8y2+16y=0 to get y(y2−8y+16)=0.The factored form of y2−8y+16 is (y−4)2, so the equation becomes y(y−4)2=0.Set each factor equal to zero: y=0 or y3−8y2+16y−x2+2x=00. Solving y3−8y2+16y−x2+2x=00 gives y3−8y2+16y−x2+2x=02.
Final Y-Coordinate: Substitute x=0 into the original equation y3−8y2+16y−x2+2x=0 to get y3−8y2+16y=0.Factor out y from the equation y3−8y2+16y=0 to get y(y2−8y+16)=0.The factored form of y2−8y+16 is (y−4)2, so the equation becomes y(y−4)2=0.Set each factor equal to zero: y=0 or y3−8y2+16y−x2+2x=00. Solving y3−8y2+16y−x2+2x=00 gives y3−8y2+16y−x2+2x=02.The y-value that satisfies the original equation when x=0 is y3−8y2+16y−x2+2x=02. This is the y-coordinate of the point where the line tangent to the curve is the y-axis.
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