x的平方减去5x减去2007等于0,求x-2分之(x-2)的三次方-(x-1)的平方加1的值 要完整的过程..
问题描述:
x的平方减去5x减去2007等于0,求x-2分之(x-2)的三次方-(x-1)的平方加1的值 要完整的过程..
答
x^2-5x-2007=0,x^2-5x+25/4-2007-25/4=0,
(x-5/2)^2-8003/4=0,(x-5/2)^2=8003/4,x-5/2=+/-根号8003/4
x=5/2+/-1/2根号8003
(x - 2)^3/(x - 2) - (x - 1)^2 + 1 = - 2x + 4=-1+/-根号8003
答
(x - 2)^3/(x - 2) - (x - 1)^2 + 1 = - 2x + 4
解方程,得到:
x1=1/2 (5 - √8053)
x2=1/2 (5 + √8053)
值就等于-1 + √8053或-1 - √8053
答
化简:(x - 2)^3/(x - 2) - (x - 1)^2 + 1 = - 2x + 4.设:- 2x + 4=a,则:x=2-(1/2)a,代入:x^2-5x-2007=0,再化简得:a1=-1+√8053,a2=-1-√8053;检验知:a2=-1-√8053不合题意,舍去.即:x-2分之(x-2)的三次方-(x-1)的平方加1的值=a1=-1+√8053.