Q. Find the equation of the tangent line to x=3t and y=21(t2−2) at the point (2,31)
Find Derivative: To find the equation of the tangent line, we need to find the derivative of y with respect to x. This can be done by finding dtdy and dtdx and then dividing dtdy by dtdx to get dxdy.
Calculate dtdx: First, let's find dtdx. Given x=3t, we differentiate with respect to t to get dtdx=31t−32.
Calculate dtdy: Now, let's find dtdy. Given y=21(t2−2), we differentiate with respect to t to get dtdy=t.
Find dxdy: Next, we find dxdy by dividing dtdy by dtdx. So, dxdy=dtdxdtdy=(31t−32)t=3t35.
Find t Value: We need to find the value of t that corresponds to the point (2,31). Since x=3t, we solve the equation 2=3t to find t. Cubing both sides gives us t3=8, so t=2.
Calculate Slope: Now we substitute t=2 into the derivative dxdy to find the slope of the tangent line at the point (2,31). The slope m is 3∗(2)35.
Use Point-Slope Form: Calculating the slope m, we get m=3⋅(2)35=3⋅(235)=3⋅(22⋅231)=3⋅4⋅32=12⋅32.
Substitute Values: With the slope m=1232 and the point (2,31), we can use the point-slope form of the equation of a line to find the equation of the tangent line: y−y1=m(x−x1), where (x1,y1) is the point (2,31).
Simplify Equation: Substituting the values into the point-slope form, we get y−31=1232(x−2).
Final Tangent Line Equation: To simplify, we distribute the slope on the right side of the equation: y−31=1232x−2432.
Final Tangent Line Equation: To simplify, we distribute the slope on the right side of the equation: y−31=1232x−2432. Finally, we add 31 to both sides to get the equation of the tangent line in slope-intercept form: y=1232x−2432+31.
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