- #36
learningphysics
Homework Helper
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Still a few careless mistakes there.
You're welcome. Great for me too. get some sleep. See you tomorrow...
You're welcome. Great for me too. get some sleep. See you tomorrow...
munkachunka said:hi,
I attempted to solve by completing the square but it all went a bit crazy.
got it to
33.56t^2-918.88t+211085.1=217482.7
I do not know how to convert the left hand side to square form, the times I have done this before I could just see the answer.
I am not sure how to solve using the derivative, do you mean differentiate?
i.e D^2= 33.56t^2-918.88t+6397.57 = D^2=67.12t-918.88
(or would it be 2D=67.12t-918.88)?
munkachunka said:67.12t-918.88 = 0.
therefore t=918.88/67.12
t=13.69
not sure what you mean by "then get R at the t value you get" so close but so far
munkachunka said:thats great! I can now see what the method is for this type of question, would I be able to get just a few more mins of your time, could you explain why I had to differentiate and set it to 0?, I know the distance formula was used to get the closest point of the 2 vectors and the result of this was a quadratic which we then differentiated and solved for D.
I think my main issue is that I don't understand how the 2 vectors get turned into a parabola which gives the 2 points. does each parabola's side represent 1 vector?
thanks a million
munkachunka said:i think you explained that very well yourself, thanks again for your time and definatly your patience!