✔ 最佳答案
2x^4+x^3-11x^2+x+2=0
using synthetic division
2|....2.....1...- 11...1...2
.............4......10..-2..-2
-------------------------------------
......2......5....-1...-1...0
(2x^3 + 5x^2 - x - 1)(x - 2) = 0
1/2 |....2....5....- 1...-1
................1......3....1
---------------------------------
...........2...6.....2.....0
(2x^2 + 6x + 2)(x - 2)(2x - 1) = 0
x^2 + 3x + 1 = 0
x^2 + 3x = - 1
x^2 + 3x + 9/4 = - 1 + 9/4
(x + 3/2)^2 = 5/4
x + 3/2 = ± √(5/4)
x = - 3/2 ± √(5)/2
x = 1/2[- 3 + √(5)], 1/2[-3 - √(5)], 2, 1/2 answer//