Question

solve for x
0=(24x^3)-(72x^2)-(186x)+360

solve for x
0=(24x^3)-(72x^2)-(186x)+360
@Mathematics

Answer 1

x1= -5/2, x2=3/2, x3=4

Answer 2

(24x^3)-(72x^2)-(186x)+360 = x^3 - 3x^2 - 31x/4 +15
First we find one root by guessing or plotting the polynomial, and we see that one root is x = 4. Then we solve the rest as follows:

(x^3 - 3x^2 - 31x/4 +15)/(x-4) = x^2 + x - 15/4
(x-4)(x^2 + x - 15/4) = 0
d = b^2 -4ac = 1 - 4*1*(-15/4) = 16
x = (-b+-sqrt(d))/2a = (-1+-4)/2, so x = -5/2 or x = 3/2

Answer 3

because we know that (x-4) = 0