http://goo.gl/DATSi3 check this example question.
I don't understand where the "(0.002x)x" come from.

Question

http://goo.gl/DATSi3 check this example question.
I don't understand where the "(0.002x)x" come from.

vincent-lyon.fr · Answer

derivation of x² with respect to time gives 2.x.dx/dt

so  0.001 becomes 0.002 because of the factor 2 that appeared in the derivation process.

anonymous · Answer

ahhh, derivation... didn't see tha coming :)

anonymous · Answer

now I don't understand how the Vx appear

vincent-lyon.fr · Answer

$v_x$ , or horizontal component of the velocity, is the same as the $dx/dt$ that appears in the equation.
Whereas $v_y$ = 10 m/s is given in the question.

anonymous · Answer

Ah... right, part of calculus. I think I get it now.
I need to relearn my calculus again.
Thanks for your help, Mr. Vincent. :)