3x^4-18x^3+9x^2-54x
ax (x^2+b) (x+c)

what is the value of c

To find the inverse of a number a, one can use the equation f(c) = a-1/c=0 where c is the inverse of a use the secant method of finding roots of equations to find the inverse of a = 2.5 ,er = 0.001%