If it's not what You are looking for type in the equation solver your own equation and let us solve it.
D( a )
2*a^4 = 0
2*a^4 = 0
2*a^4 = 0
2*a^4 = 0 // : 2
a^4 = 0
a = 0
a in (-oo:0) U (0:+oo)
(10*a^9)/(2*a^4) = 0
5*a^5 = 0 // : 5
a^5 = 0
a = 0
a in { 0}
a belongs to the empty set
| -2-2*7=-16 | | 5d+4c=38 | | 40000=52(40x+10(1.5x)) | | 0=12x^8-72x^6 | | 8(x-1)=-6(x+4)+40 | | 3d+7c=32 | | 4x+7x-6x+6x= | | -6=-6(x-4)+8(x-5) | | 4(y-4)+2(y+3)=8 | | 32-5x=(-8) | | 2x+x=29 | | 2x+6x-6x+9= | | 4m+3n=25 | | 2+x=5x-10 | | -5(11x+1)=-6-24x | | 12x-4=(-100) | | 2(x/y)=10 | | 2log((x^2)+1)=4 | | 2lg((x^2)+1)=4 | | X+2x=26 | | -7(4x+2)+6x=140 | | 18-3r=-3(6r-6) | | -6(5x+2)=48 | | 8(8+3x)=-31+5x | | 2x+6x-(6x+9)= | | -4(r+8)=-3r-33 | | x/5-x/3=8 | | x/5-x/8 | | 2.25t-27t+198= | | -3(6-5b)=7b+14 | | 8x+5=89 | | 103=2x+2 |