If it's not what You are looking for type in the equation solver your own equation and let us solve it.
D( t )
t = 0
t = 0
t = 0
t in (-oo:0) U (0:+oo)
4/t = 2/3 // - 2/3
4/t-(2/3) = 0
4/t-2/3 = 0
4*t^-1 = 2/3 // : 4
t^-1 = 1/6
-1 < 0
1/(t^1) = 1/6 // * t^1
1 = 1/6*t^1 // : 1/6
6 = t^1
t = 6
t = 6
| (y-9)+y=90 | | x+1.3=7.3 | | (4x+13)=(5x-15) | | (4x+13)+(5x-15)=180 | | (3x^-1/y^2)^-3 | | (4x+13)+(5x-15)=90 | | 8x+(5x-1)=90 | | 216=2zsquared | | 16x-12/8 | | 2x+(10x-6)=90 | | 2x+(10x-6)=180 | | 2x=(10x-6) | | 2x+3x+(10x-6)=180 | | 19/x=2.71 | | 25x-7-14x+3=27x-4-16x+15 | | 4+12x=-7+x | | -3y+9=27 | | -6v=4v | | x^3*r^3+6x^2*r^2+3xr-3=0 | | x^2+y^2-10x-38=0 | | 8*y=40 | | x^2+3bx-10b^2=0 | | 2x-0=x+10 | | (x+4)(x-3)=3 | | 18q+5-6q+6= | | 6x^4+4x^2-12=0 | | x^3-4x^2+5x-3=0 | | 4x^2+5bx=-b^2 | | 20-3x=10+5x | | -3c=7.83 | | -2b=-5.94 | | x^3-10x^2+31x=34 |