What is the velocity vector of a particle traveling to the right along the hyperbola y=x^-1 with a constant speed 5cm/s when the particle's location is (2,1/2)?

Question

anonymous · Answer

find the derivative of 1/x
 sub.s in x=2; that gives you the direction of V at that point...

anonymous · Answer

length of V is 5

anonymous · Answer

|dw:1351223394658:dw|

anonymous · Answer

does that help?

anonymous · Answer

No not really, The answer in the back of the book is <20/sqrt17, -5/sqrt17> I have no idea how they got that :/

anonymous · Answer

m = rise/run = (-1/4) /1

find the unit vector of  < 1, -1/4>  and multiply it by 5

anonymous · Answer

what's the magnitude of <1 , -1/4>

anonymous · Answer

sqrt( 1^2 + (-1/4)^2)

anonymous · Answer

sqrt(17/16)

anonymous · Answer

5 * 1/(sqrt(17/16)) * <1 , -1/4>

anonymous · Answer

Thank you so much ^_^ that problem was giving me grief.

anonymous · Answer

sure:)