Question

（1+X-2分之1）÷X的平方-4分之X平方-2X+1其中X=5先化简在求值

Answer 1

是-4分之（X平方-2X+1）？

=(x-2+1)/(x-2)÷x²-（x²-2x+1）/4
=(x-1)/(x-2)x²-（x-1）²/4
=(x-1)*[1/(x-2)x²-(x-1)/4]
=(x-1)*[4/4(x-2)x²-(x-1)(x-2)x²/4(x-2)x²]
=(x-1)*[4-(x-1)(x-2)x²]/4(x-2)x²
=4*[4-4*3*25]/4*3*25
=-296/75

要是（1+X-2分之1）÷（X的平方-4分之X平方-2X+1）
=(x-2+1)/(x-2)÷[(x-1)²-x²/4]
=(x-1)/(x-2)÷[(x-1-x/2)(x-1+x/2)]
=(x-1)/(x-2)÷[(x/2-1)(3x/2-1]
=(x-1)/(x-2)÷[(x-2)/2(3x-2)/2]
=4(x-1)/(x-2)÷[(x-2)(3x-2)]
=4(x-1)/(x-2)²(3x-2)
=4*4/3²*13
=16/117

请把后面的式子用括号写清楚