ds^2 = dx^2 + dy^2
x = t^3
so dx = 3 t^2 dt and dx^2 = 9 t^6 dt^2
y = 2 sin t
dy = 2 cos t dt and dy^2 = 4 cos^2 t dt^2
ds^2 = dt^2 [ 9 t^6 + 4 cos^2 t ]
ds = [ 9t^2+4cos^2t]^2 dt
ds = [81 t^4 + 72 t^2 cos^2 t + 16 cos^4 t ] dt
s = [ (81/5)t^5 + 72(t^3/6+{t^2/4-1/8}sin 2t+tcos2t /4)+16 (sint cos^3t/4 +{3/8}costsint +3t/8) ] ... see https://socratic.org/questions/how-do-you-find-the-integral-of-cos-4-x-dx
evaluate at t = pi and t = 1 and subtract
The components of a position vector of a particle moving in the plane are components t cubed, 2 times the sine of t. What is the distance traveled by the particle from t = 1 to t = π?
Type your answer in the space below and give 3 decimal places. If your answer is less than 1, place a leading "0" before the decimal point (ex: 0.482).
Please can you show me your work? Thanks
4 answers
sorry, to the 1/2 not squared, same approach
Omg!!! I am so confuse. I guess are the parenthesis or exponents. I don't know. The example in socratic is so different. I don't get it. Please I need your help
Actually I have just done the test and got 100%
The answer is 30.113
first you do derivative of the vectors both coordinates.
Then you find the magnitude of the vector. and that magnitude is the derivative of the position function. After that you know what to do.
Just in your calc enter integral from 1 to pi of sqrt((etc)^2) and you get 30.113
The answer is 30.113
first you do derivative of the vectors both coordinates.
Then you find the magnitude of the vector. and that magnitude is the derivative of the position function. After that you know what to do.
Just in your calc enter integral from 1 to pi of sqrt((etc)^2) and you get 30.113