If it's not what You are looking for type in the equation solver your own equation and let us solve it.
D( x )
x = 0
x^2 = 0
x = 0
x = 0
x^2 = 0
x^2 = 0
1*x^2 = 0 // : 1
x^2 = 0
x = 0
x in (-oo:0) U (0:+oo)
1-(1/x) = 12/(x^2) // - 12/(x^2)
1-(1/x)-(12/(x^2)) = 0
1-x^-1-12*x^-2 = 0
t_1 = x^-1
1-12*t_1^2-1*t_1^1 = 0
1-12*t_1^2-t_1 = 0
DELTA = (-1)^2-(-12*1*4)
DELTA = 49
DELTA > 0
t_1 = (49^(1/2)+1)/(-12*2) or t_1 = (1-49^(1/2))/(-12*2)
t_1 = -1/3 or t_1 = 1/4
t_1 = -1/3
x^-1+1/3 = 0
1*x^-1 = -1/3 // : 1
x^-1 = -1/3
-1 < 0
1/(x^1) = -1/3 // * x^1
1 = -1/3*x^1 // : -1/3
-3 = x^1
x = -3
t_1 = 1/4
x^-1-1/4 = 0
1*x^-1 = 1/4 // : 1
x^-1 = 1/4
-1 < 0
1/(x^1) = 1/4 // * x^1
1 = 1/4*x^1 // : 1/4
4 = x^1
x = 4
x in { -3, 4 }
| y-6=3(x+2) | | 2w-0.4=1+1.8w | | 1-(1/x)=(12/x^2) | | d=-16t^2+80t+3.5 | | 18(4x+2-x)=36x | | -16a+a+28a= | | 4/-4+20.5=12.9 | | 2r-3(r+6)=4(r-1) | | y+3=2(x-4) | | 6x^2-16=0 | | 4*-9+9= | | 7d+3d+5d-2-3d=0 | | 2.5-4x=10-2.5x | | 4x+2=2(3x-9) | | -30=11x+3 | | 9/100+h=1/10 | | 4b+1=-15 | | 5*-5/4+9 | | Z^2-z-20=10 | | 2/9*9= | | 2(4-x)-x=36 | | -6/2 | | 1/2*8 | | -10=z-15 | | -5v=6x+5-v | | 90+1x+3x=180 | | 2k=-3(k+1)+7 | | -5+6x=1 | | (2x^2)(4y^2)+6x^2y^2= | | y^2+6y+48=0 | | 3t^2+9t-28=0 | | 5x^2+10x-4=0 |