Math Problem Statement

Find the tangent to each curve at the point where t = 3:

Solution

To find the tangent to each curve at the point where t=3t = 3, we need to know the parameterized equations of the curves. Typically, these would be given as functions of tt. For this example, let's consider we have two parameterized curves C1C_1 and C2C_2 given by:

C1:{x1(t)=f(t)y1(t)=g(t)C_1: \begin{cases} x_1(t) = f(t) \\ y_1(t) = g(t) \end{cases} C2:{x2(t)=h(t)y2(t)=k(t)C_2: \begin{cases} x_2(t) = h(t) \\ y_2(t) = k(t) \end{cases}

To find the tangent to each curve at t=3t = 3, we follow these steps:

  1. Evaluate the point on each curve at t=3t = 3: P1=(x1(3),y1(3))P_1 = (x_1(3), y_1(3)) P2=(x2(3),y2(3))P_2 = (x_2(3), y_2(3))

  2. Compute the derivatives of the parameterized functions to find the slopes: dx1dtt=3=f(3)\frac{dx_1}{dt} \Bigg|_{t=3} = f'(3) dy1dtt=3=g(3)\frac{dy_1}{dt} \Bigg|_{t=3} = g'(3) dx2dtt=3=h(3)\frac{dx_2}{dt} \Bigg|_{t=3} = h'(3) dy2dtt=3=k(3)\frac{dy_2}{dt} \Bigg|_{t=3} = k'(3)

  3. The slope of the tangent line to each curve at t=3t = 3 is given by: m1=dy1dx1=g(3)f(3)m_1 = \frac{dy_1}{dx_1} = \frac{g'(3)}{f'(3)} m2=dy2dx2=k(3)h(3)m_2 = \frac{dy_2}{dx_2} = \frac{k'(3)}{h'(3)}

  4. Write the equations of the tangents using the point-slope form of the line equation: yy1(3)=m1(xx1(3))y - y_1(3) = m_1 (x - x_1(3)) yy2(3)=m2(xx2(3))y - y_2(3) = m_2 (x - x_2(3))

Now let's illustrate this with specific parameterized functions. Assume:

C1:{x1(t)=t2y1(t)=t3C_1: \begin{cases} x_1(t) = t^2 \\ y_1(t) = t^3 \end{cases} C2:{x2(t)=sin(t)y2(t)=cos(t)C_2: \begin{cases} x_2(t) = \sin(t) \\ y_2(t) = \cos(t) \end{cases}

  1. Evaluate the points at t=3t = 3: P1=(x1(3),y1(3))=(9,27)P_1 = (x_1(3), y_1(3)) = (9, 27) P2=(x2(3),y2(3))=(sin(3),cos(3))(0.1411,0.98999)P_2 = (x_2(3), y_2(3)) = (\sin(3), \cos(3)) \approx (0.1411, -0.98999)

  2. Compute the derivatives at t=3t = 3: dx1dt=2tt=3=6\frac{dx_1}{dt} = 2t \Bigg|_{t=3} = 6 dy1dt=3t2t=3=27\frac{dy_1}{dt} = 3t^2 \Bigg|_{t=3} = 27

    dx2dt=cos(t)t=30.98999\frac{dx_2}{dt} = \cos(t) \Bigg|_{t=3} \approx -0.98999 dy2dt=sin(t)t=30.1411\frac{dy_2}{dt} = -\sin(t) \Bigg|_{t=3} \approx -0.1411

  3. Find the slopes of the tangents: m1=dy1dx1=276=4.5m_1 = \frac{dy_1}{dx_1} = \frac{27}{6} = 4.5 m2=dy2dx2=0.14110.989990.1425m_2 = \frac{dy_2}{dx_2} = \frac{-0.1411}{-0.98999} \approx 0.1425

  4. Write the equations of the tangents: y27=4.5(x9)y - 27 = 4.5(x - 9) y(0.98999)=0.1425(x0.1411)y - (-0.98999) = 0.1425(x - 0.1411)

Simplify these to get: y=4.5x13.5y = 4.5x - 13.5 y=0.1425x1.009y = 0.1425x - 1.009

These are the equations of the tangents to the curves C1C_1 and C2C_2 at t=3t = 3.

Would you like further details or have any questions about this solution?

Here are some related questions you might want to ask:

  1. How do you find the intersection points of two parametric curves?
  2. What is the chain rule, and how is it used in parametric differentiation?
  3. How do you convert a parametric equation to Cartesian form?
  4. How do you find the arc length of a parametric curve?
  5. What are some applications of parametric equations in real life?

Tip: When dealing with parametric equations, always check the derivatives to understand the behavior and slope of the curve at any given point.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Parametric Equations
Derivatives
Tangent Lines

Formulas

Point-Slope Form of a Line Equation

Theorems

-

Suitable Grade Level

Advanced High School