x^3+6x^3+11x+6初二分解因式,

x^3+6x^3+11x+6初二分解因式,


X^3+6X^2+11X+6
=(X^3+X^2)+(5X^2+5X)+(6X+6)
=X^2(X+1)+5X(X+1)+6(X+1)
=(X+1)(X^2+5X+6)
=(X+1)(X+2)(X+3)



x^5-x^4-11x^3+11x^2+18x-18=


x^5-x^4-11x^3+11x^2+18x-18
=x^4(x-1)-11x^2(x-1)+18(x-1)
=(x-1)(x^4-11x^2+18)
=(x-1)(x^2-9)(x^2-2)
=(x-1)(x+3)(x-3)(x^2-2)(有理數範圍內)
=(x-1)(x+3)(x-3)(x+√2)(x-√2)(實數範圍內)



方程5X的平方+11X+7的根的情况是?
x指的是“埃克斯”


無根