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)
(4*x)/15 = 60/x // - 60/x
(4*x)/15-(60/x) = 0
(4*x)/15-60*x^-1 = 0
4/15*x^1-60*x^-1 = 0
(4/15*x^2-60*x^0)/(x^1) = 0 // * x^2
x^1*(4/15*x^2-60*x^0) = 0
x^1
(4/15)*x^2-60 = 0
(4/15)*x^2-60 = 0
DELTA = 0^2-(-60*4*(4/15))
DELTA = 64
DELTA > 0
x = (64^(1/2)+0)/(2*(4/15)) or x = (0-64^(1/2))/(2*(4/15))
x = 15 or x = -15
x in { -15, 15}
x in { -15, 15 }
| 1.6x-1.2+x-4.1= | | x(-12)=3 | | x(-12)=13 | | (3)/(7)=(12)/x | | 3/4÷5/4 | | .6n+12=2n-9 | | 7/9=1/3x | | F(x)=lx^2-25l | | 3(8x-3)= | | 3x^5+4x^3+2x+3=0 | | 35-2ln(4m+25)=2 | | f(x)=9x^2-12x | | 6(y-2x)=0 | | 4ln(8x)=20 | | V/9-4=14 | | 2x-3y=120 | | x/7=1/4 | | 3x+(x-1)=50 | | x/14=45/35 | | 3+2(X-1)=1 | | 1+3b=16 | | (4-3)ln(x)=5 | | x^2+(1-2k)-2k=0 | | 28=13x+51 | | x^2+3x+4=34+10x-x^2 | | -7=12+3 | | 0.625-3.125=x | | 0.625-3.125= | | 34+10x-x^2=x^2+3x+4 | | X^2+37x+2=0 | | x^2-4xy-5y^2=2 | | 6+5(2-x)=-3(x+4) |