The length of a curve defined in polar coordinates can be calculated using the formula:
L = ∫ab √( (dr/dt)^2 + (r^2) ) dt
Where:
- r(t) is the radius as a function of t,
- Theta (θ) is the angle related to the radius,
- dr/dt is the derivative of r with respect to t,
- L is the length of the curve from t=a to t=b.
To find the length of the specified curve:
- Differentiate r(t): r(t) = 7t
- Calculate dr/dt: dr/dt = 7
- Express r(t) in terms of t: r(t) = 7t
- Now, substitute these values into the length formula:
- Calculate the definite integral from the limits of integration you choose for t.
L = ∫ab √( (7)^2 + (7t)^2 ) dt = ∫ab √ (49 + 49t^2) dt = ∫ab 7√(1 + t^2) dt
Finally, evaluating the integral will provide the length of the curve for the specified range.