If it's not what You are looking for type in the equation solver your own equation and let us solve it.
D( x )
15-((x/3)*x^5) = 0
15-((x/3)*x^5) = 0
15-((x/3)*x^5) = 0
(-1/3)*x^6+15 = 0
-1/3*x^6 = -15 // : -1/3
x^6 = 45
x^6 = 45 // ^ 1/6
abs(x) = 45^(1/6)
x = 45^(1/6) or x = -45^(1/6)
x in (-oo:-45^(1/6)) U (-45^(1/6):45^(1/6)) U (45^(1/6):+oo)
(x-((15/9)*x))/(15-((x/3)*x^5)) = 0
(x+(-5/3)*x)/((-1/3)*x^6+15) = 0
(-2/3*x)/(15-1/3*x^6) = 0
-2/3*x = 0 // : -2/3
x = 0
x = 0
| y=5x+15(-3) | | 5v^2x^3w/3v^2 | | 2(3c-1)-5=4c+5 | | 49x^2+9=73 | | 24+4f=-8 | | 4+5-6y+y= | | x=-3(4+2)-7 | | 6p^2+5=389 | | 20+-f=-12 | | -12-4(6m+12)=4(-7m+1) | | -2(6-3x)=8x+2 | | (5x^2-4)/(6x^2-6)=0 | | 18+3(j+4)= | | 8(1+j)= | | r^2+2rs= | | -3t-15=-9 | | 8y+32=-4(y+7) | | 11(x+9)=-(11-6x) | | -6x-27=-8x+33 | | 12/(3+1)=5 | | 8x^2+20y= | | 3x+-168=21 | | 11x-142=124-3x | | 2*3.14*7.79= | | 25y+30x=1800 | | 3(4x-2)+5=4x-1 | | 35x+25y=1800 | | 2x-6x+2x-7+3x= | | 21=12z-15 | | 4x^3+4x^2-36x-36=0 | | x^2+7-1=0 | | 9x-96=3x+72 |