-4/w-4=-1/5w-20+1

Solution for -4/w-4=-1/5w-20+1 equation:

D( w )

w = 0

w = 0

w = 0

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

-4/w-4 = (-1/5)*w-20+1 // - (-1/5)*w-20+1

20-((-1/5)*w)-4/w-4-1 = 0

(1/5)*w-4/w-4-1+20 = 0

1/5*w^1-4*w^-1+15*w^0 = 0

(1/5*w^2+15*w^1-4*w^0)/(w^1) = 0 // * w^2

w^1*(1/5*w^2+15*w^1-4*w^0) = 0

w^1

(1/5)*w^2+15*w-4 = 0

(1/5)*w^2+15*w-4 = 0

DELTA = 15^2-(-4*4*(1/5))

DELTA = 1141/5

DELTA > 0

w = ((1141/5)^(1/2)-15)/(2*(1/5)) or w = (-(1141/5)^(1/2)-15)/(2*(1/5))

w = 5/2*((1141/5)^(1/2)-15) or w = -5/2*((1141/5)^(1/2)+15)

w in { -5/2*((1141/5)^(1/2)+15), 5/2*((1141/5)^(1/2)-15)} 

w in { -5/2*((1141/5)^(1/2)+15), 5/2*((1141/5)^(1/2)-15) }