已知x=4-根号3,求(x的四次方-6x的三次方-2x²+18x+23)/(x²-8x+15)的值

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已知x=4-根号3,求(x的四次方-6x的三次方-2x²+18x+23)/(x²-8x+15)的值
已知x=4-根号3,求(x的四次方-6x的三次方-2x²+18x+23)/(x²-8x+15)的值

已知x=4-根号3,求(x的四次方-6x的三次方-2x²+18x+23)/(x²-8x+15)的值
x=4-√3
x-4=-√3(平方)
x²-8x+16=3
x²-8x+13=0
(x^4-6x^3-2x^2+18x+23)/(x^2-8x+15)
=[x^2(x^2-8x+13)+2x^3-15x^2+18x+23]/(x^2-8x+15)
=[2x(x^2-8x+13)+x^2-8x+23]/(x^2-8x+15)
=[x^2-8x+23]/(x^2-8x+13+2)
=(x^2-8x+13+10)/(0+2)
=(0+10)/2
=5