2/7=v-3/v

Solution for 2/7=v-3/v equation:

D( v )

v = 0

v = 0

v = 0

v in (-oo:0) U (0:+oo)

2/7 = v-(3/v) // - v-(3/v)

3/v-v+2/7 = 0

3*v^-1-1*v^1+2/7*v^0 = 0

(2/7*v^1-1*v^2+3*v^0)/(v^1) = 0 // * v^2

v^1*(2/7*v^1-1*v^2+3*v^0) = 0

v^1

(2/7)*v-v^2+3 = 0

(2/7)*v-v^2+3 = 0

DELTA = (2/7)^2-(-1*3*4)

DELTA = 592/49

DELTA > 0

v = ((592/49)^(1/2)-(2/7))/(-1*2) or v = (-(2/7)-(592/49)^(1/2))/(-1*2)

v = ((592/49)^(1/2)-2/7)/(-2) or v = ((592/49)^(1/2)+2/7)/2

v in { ((592/49)^(1/2)-2/7)/(-2), ((592/49)^(1/2)+2/7)/2} 

v in { ((592/49)^(1/2)-2/7)/(-2), ((592/49)^(1/2)+2/7)/2 }