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 = 0
x = 0
x = 0
x in (-oo:0) U (0:+oo)
40/x-(40/x)-6 = 7/x // - 7/x
40/x-(40/x)-(7/x)-6 = 0
40/x-40*x^-1-7*x^-1-6 = 0
-7*x^-1 = 6 // : -7
x^-1 = -6/7
-1 < 0
1/(x^1) = -6/7 // * x^1
1 = -6/7*x^1 // : -6/7
-7/6 = x^1
x = -7/6
x = -7/6
| 7x-28/5=2x | | 2(w-6)/9=2 | | 3f+7=-11 | | 8x+16=5x+15 | | 1/2ln2 | | x^2-4x=x+24 | | x-19/x-203 | | h(x)=3*-5+5 | | 6(j+434)=984 | | x^2+5x+5x+24=0 | | (3x-5)x=0 | | 19(r+954)=266 | | y=26-4*6 | | y=26-4*5 | | x+8=1008 | | r^2+10r+35=0 | | y=26-4*4 | | 7x-9=7(x-1)-2 | | 20/14=90/t | | y=26-4*2 | | T^2=4t+6 | | y=26-42 | | y-12=2x^2+8x+8 | | 19b-(-29)=352 | | 2x+14=5+2x+(x+3) | | x*2+14=5+2x+(x+3) | | 3+5u=-32 | | 11+r=9x-4 | | x+21=5+2x+(x+3) | | 6x^2-12x-33=3 | | -12=2v-4 | | 9(k+4)=81 |