4/n^2=7/n+2

Solution for 4/n^2=7/n+2 equation:

D( n )

n = 0

n^2 = 0

n = 0

n = 0

n^2 = 0

n^2 = 0

1*n^2 = 0 // : 1

n^2 = 0

n = 0

n in (-oo:0) U (0:+oo)

4/(n^2) = 7/n+2 // - 7/n+2

4/(n^2)-(7/n)-2 = 0

4/(n^2)-7*n^-1-2 = 0

4*n^-2-7*n^-1-2 = 0

t_1 = n^-1

4*t_1^2-7*t_1^1-2 = 0

4*t_1^2-7*t_1-2 = 0

DELTA = (-7)^2-(-2*4*4)

DELTA = 81

DELTA > 0

t_1 = (81^(1/2)+7)/(2*4) or t_1 = (7-81^(1/2))/(2*4)

t_1 = 2 or t_1 = -1/4

t_1 = -1/4

n^-1+1/4 = 0

1*n^-1 = -1/4 // : 1

n^-1 = -1/4

-1 < 0

1/(n^1) = -1/4 // * n^1

1 = -1/4*n^1 // : -1/4

-4 = n^1

n = -4

t_1 = 2

n^-1-2 = 0

1*n^-1 = 2 // : 1

n^-1 = 2

-1 < 0

1/(n^1) = 2 // * n^1

1 = 2*n^1 // : 2

1/2 = n^1

n = 1/2

n in { -4, 1/2 }