If it's not what You are looking for type in the equation solver your own equation and let us solve it.
D( z )
z-1 = 0
z-1 = 0
z-1 = 0
z-1 = 0 // + 1
z = 1
z in (-oo:1) U (1:+oo)
(0.5/(z-1))*(z+0)^2 = 0
z^2*(0.5/(z-1)) = 0
(0.5*z^2)/(z-1) = 0
1*z^2 = 0 // : 1
z^2 = 0
z = 0
z = 0
| 2(x-1)=8x-14 | | y=4(y+2)+1 | | (4x-5)^1/3-6=-4 | | 4x-6=x-15 | | x=6.428571429 | | 4=6/7t+1 | | 0=18/7x | | -5/3s+11/2=27/4 | | -8+4+1/8b | | 9x-20+2=18 | | 4A=44 | | 4c^3+20c^2-96c=0 | | 30x^2+w-20=0 | | 45/16=13/8-1/2x | | x/3=-17 | | 3/x^2-2/x+3 | | (1/x-3)-(2/x+3)=1/x^2-9 | | 11+15x=-17+13x | | 5/11t-3=16/11 | | 6(y+1)=-y+7 | | 3x^2+7y+3=0 | | 3(4c-1)-3=10c+2 | | 6=x+20/7 | | 6x^4+5x^3-11x^2-13x-3=0 | | 24=2w+2(4+w) | | 3w^2+w=20 | | 1*(5+1/2)*4 | | 10=6+5/3t | | -1+2/5t=-3/5 | | 4/3x-9=-6 | | 1*5+1/2*4 | | -y=3/5 |