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## Main Question or Discussion Point

A particle of mass m is subject to a force F(v) = bv^2. The initial position is zero, and the initial speed is vi find x(t)

so far

m*dv/dx*v = -bv^2

m*dv/dx = -bv

integral m/-bv*dv = integral dx

m/-b*ln(v) + a = x + b

What do I do with the constants? i thought i was suppose to put in 'a' as vi and b as 0, but then when i integrate again for v, so i can get x(t) function, what do i use to fill in that constant?

so far

m*dv/dx*v = -bv^2

m*dv/dx = -bv

integral m/-bv*dv = integral dx

m/-b*ln(v) + a = x + b

What do I do with the constants? i thought i was suppose to put in 'a' as vi and b as 0, but then when i integrate again for v, so i can get x(t) function, what do i use to fill in that constant?