If it's not what You are looking for type in the equation solver your own equation and let us solve it.
D( r )
r = 0
r = 0
r = 0
r in (-oo:0) U (0:+oo)
3*r-(2/r) = 9/6 // - 9/6
3*r-(2/r)-(9/6) = 0
3*r-2*r^-1-3/2 = 0
3*r^1-2*r^-1-3/2*r^0 = 0
(3*r^2-3/2*r^1-2*r^0)/(r^1) = 0 // * r^2
r^1*(3*r^2-3/2*r^1-2*r^0) = 0
r^1
3*r^2+(-3/2)*r-2 = 0
3*r^2+(-3/2)*r-2 = 0
DELTA = (-3/2)^2-(-2*3*4)
DELTA = 105/4
DELTA > 0
r = ((105/4)^(1/2)-(-3/2))/(2*3) or r = (-(-3/2)-(105/4)^(1/2))/(2*3)
r = ((105/4)^(1/2)+3/2)/6 or r = (3/2-(105/4)^(1/2))/6
r in { (3/2-(105/4)^(1/2))/6, ((105/4)^(1/2)+3/2)/6}
r in { (3/2-(105/4)^(1/2))/6, ((105/4)^(1/2)+3/2)/6 }
| 8x^2-7x^3-5x^2-9x^3=0 | | 1c=5c+4 | | 2/5x-4=22 | | 4x+(2x-3)= | | 3n-5n= | | 1/x-(1/x-4) | | 1/x-1/x-4 | | 3(5x+4)-9x=2(3x+6)-16 | | (7x)+(2x+8)+(x+2)=180 | | 2x+25=6x+21 | | 3(5s+4)-9s=2(3s+6)-16 | | 6s+8=6s | | -4y-10=30 | | -24+8y=40 | | x^4-x^3-3x^2-54=0 | | y=3x+30 | | 6(x-4)=x+2 | | 2(2x+4)=-3(2x+1) | | 180-(2+39)=79 | | (-30(-7))-(-210(-3))= | | 5/6c+2/15=-7/10 | | a^3-3a^2-4a+12=0 | | 5/6c+2/15=7/10c | | y=x^2-36 | | 8r-5r+2=6r-r | | 2h-3m=16 | | 2(x-4)+2x=6x-2 | | (15-4x)/4 | | 2(x-4)+2x=-6x-4 | | 12-(-5m)+3m+12=0 | | 4x=54-4x | | 6(5y+3)=13-2x |