If it's not what You are looking for type in the equation solver your own equation and let us solve it.
D( x )
x-3 = 0
x^2-9 = 0
x+3 = 0
x-3 = 0
x-3 = 0
x-3 = 0 // + 3
x = 3
x^2-9 = 0
x^2-9 = 0
1*x^2 = 9 // : 1
x^2 = 9
x^2 = 9 // ^ 1/2
abs(x) = 3
x = 3 or x = -3
x+3 = 0
x+3 = 0
x+3 = 0 // - 3
x = -3
x in (-oo:-3) U (-3:3) U (3:+oo)
1/(x-3)+1/(x+3) = 12/(x^2-9) // - 12/(x^2-9)
1/(x-3)+1/(x+3)-(12/(x^2-9)) = 0
1/(x-3)+1/(x+3)-12*(x^2-9)^-1 = 0
1/(x-3)+1/(x+3)-12/(x^2-9) = 0
(1*(x+3)*(x^2-9))/((x-3)*(x+3)*(x^2-9))+(1*(x-3)*(x^2-9))/((x-3)*(x+3)*(x^2-9))+(-12*(x-3)*(x+3))/((x-3)*(x+3)*(x^2-9)) = 0
1*(x+3)*(x^2-9)+1*(x-3)*(x^2-9)-12*(x-3)*(x+3) = 0
2*x^3-12*x^2-18*x+108 = 0
2*x^3-12*x^2-18*x+108 = 0
2*(x^3-6*x^2-9*x+54) = 0
x^3-6*x^2-9*x+54 = 0
{ 1, -1, 2, -2, 3, -3, 6, -6, 9, -9, 18, -18, 27, -27, 54, -54 }
1
x = 1
x^3-6*x^2-9*x+54 = 40
1
-1
x = -1
x^3-6*x^2-9*x+54 = 56
-1
2
x = 2
x^3-6*x^2-9*x+54 = 20
2
-2
x = -2
x^3-6*x^2-9*x+54 = 40
-2
3
x = 3
x^3-6*x^2-9*x+54 = 0
3
x-3
x^2-3*x-18
x^3-6*x^2-9*x+54
x-3
3*x^2-x^3
54-3*x^2-9*x
3*x^2-9*x
54-18*x
18*x-54
0
x^2-3*x-18 = 0
DELTA = (-3)^2-(-18*1*4)
DELTA = 81
DELTA > 0
x = (81^(1/2)+3)/(1*2) or x = (3-81^(1/2))/(1*2)
x = 6 or x = -3
x in { -3, 6, 3}
2*(x+3)*(x-6)*(x-3) = 0
(2*(x+3)*(x-6)*(x-3))/((x-3)*(x+3)*(x^2-9)) = 0
(2*(x+3)*(x-6)*(x-3))/((x-3)*(x+3)*(x^2-9)) = 0 // * (x-3)*(x+3)*(x^2-9)
2*(x+3)*(x-6)*(x-3) = 0
( x+3 )
x+3 = 0 // - 3
x = -3
( x-3 )
x-3 = 0 // + 3
x = 3
( x-6 )
x-6 = 0 // + 6
x = 6
x in { -3}
x in { 3}
x = 6
| -2/5(x-500)=-1/2x+1/10(x+2000) | | x^2-2/x=0 | | -4(-3b-2)-2=66 | | x^2-2/x+0 | | 2Q-7= | | 3x^2+3x+15=0 | | 24x2y^13/-2x^5y^2 | | J/4-5=10 | | 4(5+3x)-1=79 | | 8-2y=2y-2 | | 2-(4x+5)=3[(9x-5)-(x-8)] | | 5x^2-2=3x | | -2(3y-7)-y=-2(y-5) | | 3/2g=1/10 | | x+27=3x+11 | | 2x+y=180fory | | ((x-2)/4)-((x+5)/6)=((5x-2)/9) | | 11x+5=2x-4 | | 3+2/x=8 | | 2/3p+11=14 | | -25=4+x | | 0.25r-1.25=0.55-0.35r | | 2+5(-3+2v)=-63 | | 1/2x+5/4y=8 | | 12.5=t/h | | 1/(x-3)+1/(x+3)=18/(x^2-9) | | 7x/x-2+2x/x-2=9 | | ((5-2x)/5)+((x-4)/10)=3/10 | | 2(2k-5)-3(5k+2)=3-2(k+2) | | 8-3r=-25 | | 3x+4-2x-1=7 | | -1.6-0.9w=11.6+24w |