If it's not what You are looking for type in the equation solver your own equation and let us solve it.
D( x )
27*x*y^7 = 0
27*x*y^7 = 0
27*x*y^7 = 0
27*x*y^7 = 0 // : 27*y^7
x = 0
x in (-oo:0) U (0:+oo)
(9*x^6*y^3)/(27*x*y^7) = 0
1/3*x^5*y^-4 = 0 // : 1/3*y^-4
x^5 = 0
x = 0
x in { 0}
x belongs to the empty set
| 6/X-1 | | y=sinex | | a-a^2-a-6/2(a-3) | | 10+50x=300 | | 55x-44=52x+91 | | (-5)=4+z+z | | -6n^4+3n^4= | | 7x-4+6x-6=36 | | 72=P(.03) | | x-9=x^2-9 | | (x^2+10x+25)+(y^2+6y+9)=0 | | 13/4=x/6 | | 72=P(.04)(.75) | | (3x+y+6)dx+(2x+y+1)dy=0 | | 7x+x+23x+20x= | | 9x^2+6y^2+36y=3 | | b-1/3=7/12 | | (x+35)=-7 | | 7x-7+14x-4=14x-56 | | 3a+10+a=90 | | 1.3*0.15/100= | | 1.3x.15/100 | | 180-126= | | 5x-(-7)-11x+3=x-25 | | 126+x=180 | | 36+4x=140 | | 225/3 | | (3x^3y)^2/-9x^2y | | 48/28 | | 6x^2-17x+11=-5+3x | | x^2-y^2-2x+4y=4 | | -18x^5/12x^2 |