If it's not what You are looking for type in the equation solver your own equation and let us solve it.
D( x )
9*x = 0
9*x = 0
9*x = 0
9*x = 0 // : 9
x = 0
x in (-oo:0) U (0:+oo)
1/(9*x) < 1 // - 1
1/(9*x)-1 < 0
1/9*x^-1 < 1
1/9*x^-1 < 1 // : 1/9
x^-1 < 1/1/9
x^-1 < 9
1/(x^1) < 9
x <> 0
1/(x^1) < 9 // * x^2
(x^2)/(x^1) < 9*x^2
x^1 < 9*x^2
x-9*x^2 < 0
x^1*(1-9*x) < 0
x < 0
-(abs(x))^1*(9*(abs(x))^1+1) < 0 // : -(abs(x))^1
9*(abs(x))^1+1 > 0
9*(abs(x))^1 > -1 // : 9
(abs(x))^1 > -1/9
(abs(x))^1 > -1/9 // ^ 1/1
abs(x) > (-1/9)^(1/1)
abs(x) > -1/9
x in (-oo:0)
x < 0
x > 0
x^1*(1-(9*x^1)) < 0 // : x^1
1-(9*x^1) < 0
1 < 9*x^1 // : 9
1/9 < x^1 // ^ 1/1
(1/9)^(1/1) < x
x in (1/9:+oo)
x > 0
x in (-oo:0) U (1/9:+oo)
x in (-oo:0) U (1/9:+oo)
(-oo:0) U (1/9:+oo)
| 5205+1904-90*90= | | 5(x-3)=2(x+17)-x | | 12+5m=62 | | 5s-6(3b-1)=-11 | | 16/t=20/13.5 | | 8*x=10*48.46 | | X^3-2x^2-x-12=0 | | 2x*3=180 | | 18/57=12/z | | 2x-33=x-33 | | sinx+sin(3x)=0 | | -10x+9+10x= | | 20-(3c+4)=5c | | 1.9q-3.8-4.1q=3.2q-4.6 | | 3/5=405/q | | 80.5=3x-3x-8x-20.5 | | 6cosx-1=2 | | 0.4x+0.8=-1.2 | | p/5.6=9/2.8 | | 6x+5x=2x+18 | | 0.3x+0.6=-2.1 | | 12-p=126 | | =7a-3b+5a+6b | | 22/21=550/n | | 18c+5-6c=53 | | 75/30=10/c | | f(x)=4(-4)-5 | | 4/11=g/209 | | 19+w=14 | | 2.2+w=6.2 | | 8x+18-14x=-10+4x+14 | | 5(6x+3)(2x+5)=0 |