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 = 0
z = 0
z = 0
z in (-oo:0) U (0:+oo)
50/z-(50/z)-9 = 3/z // - 3/z
50/z-(50/z)-(3/z)-9 = 0
50/z-50*z^-1-3*z^-1-9 = 0
-3*z^-1 = 9 // : -3
z^-1 = -3
-1 < 0
1/(z^1) = -3 // * z^1
1 = -3*z^1 // : -3
-1/3 = z^1
z = -1/3
z = -1/3
| 4(x+7)+6x=10x-28 | | cosx*sin(2x)=0 | | 2.8y+6+0.2y= | | 13-t+t=t-7 | | 2w-2=4 | | 27=10+S | | 5(x-7)=35 | | (2x+6)(x+6)=0 | | 2.4x-12=24 | | 85=2x-13 | | 2/3-(9×-1/3)=5/3-11x | | 4-p=-5+p | | (7x-1)(7x-1)=-1 | | 5x^2-10=-190 | | 36-8x=100 | | Y=-2(3)+9 | | 4-(5-3x)=3x-1-(x-8) | | 12=-18+6Z | | X^3+125+5X(X+5)=0 | | 4t-9t-9=0 | | x^4-2x^2+24=0 | | 2x=-y+9 | | 6x+8-2x(7-2)=2(6+11) | | 10x^6-40x^2=0 | | 3x*(6x)=107 | | 8m^5n^9/2mn^3 | | 2(3+3x)-3=39 | | 3x+6x=107 | | -10x-7=47 | | x-8=7-4x | | 16-1/3x=6 | | 7(4z-11)-5(1+2z)=41+3(2z+7) |