If it's not what You are looking for type in the equation solver your own equation and let us solve it.
D( h )
h = 0
h = 0
h = 0
h in (-oo:0) U (0:+oo)
39/2 = 429/h // - 429/h
39/2-(429/h) = 0
39/2-429*h^-1 = 0
-429*h^-1 = -39/2 // : -429
h^-1 = 1/22
-1 < 0
1/(h^1) = 1/22 // * h^1
1 = 1/22*h^1 // : 1/22
22 = h^1
h = 22
h = 22
| f(x)=(x^3)-4 | | 6-2b=-b | | (2a+1)(2a-1)= | | 2/x=25/75 | | X=144+x-10 | | x/2=x-4/30 | | 48/1=300/y | | 40-8a=7(-2-5a) | | -z+9=-7z-9 | | x/9=3/10 | | 6/45=10/l | | 39=7n-3 | | 6w-2=2w | | 9m^2-73m+8=0 | | 7.3y-5.18=-15.9 | | 12/16=18/h | | 9m^2-72m+8=0 | | cos^2x-3cos+2=0 | | 0.3x+-0.02x+0.2=1.18 | | 2-6x=1-8 | | Log[5](x-7)=log[5](x-3)+1 | | 2k-7=j | | 60=5z-10 | | 5x+6y=300 | | 8x=-11+5x-6 | | -10-4u=-2+10 | | 12m-5=2-5m | | Bv-10=9 | | 9m^2-73x+8=0 | | 400-32x5/9 | | 0.3x-0.2x+0.2=1.18 | | 35=-2c-15 |