求数学书16.3第一题解方程答案.(1)1/x=5/x+3(2)x/x-1=3/2x-2 -2(3) 2/2x-1=4/4x2(4)3/x2+2x - 1/x2-2x =0(5) x/x-3=x+1/x-1(6)x-3/x-2+1=3/2-x(7)2x+1/x2+x=5/6x+6(8)3/2-1/3x-1=5/6x-2

问题描述:

求数学书16.3第一题解方程答案.
(1)1/x=5/x+3
(2)x/x-1=3/2x-2 -2
(3) 2/2x-1=4/4x2
(4)3/x2+2x - 1/x2-2x =0
(5) x/x-3=x+1/x-1
(6)x-3/x-2+1=3/2-x
(7)2x+1/x2+x=5/6x+6
(8)3/2-1/3x-1=5/6x-2

(1)方程两边同乘x(x+3),得x+3=5x,x-5x=-3,-4x=-3,x=3/4.
(2)方程两边同成2(x-1),得2x=3-4(x-1),2x=3-4x+4,2x+4x=3+4,6x=7,x=7/6
(3)方程两边同乘(2x-1)(2x+1),得2(2x+1)=4,4x+2=4,4x=4-2,4x=2,x=1/2
(4)方程两边同乘x(x+2)(x-2),得3(x-2)-(x+2)=0,3x-6-x-2=0,3x-x=6+2,2x=8,x=4
(5)方程两边同乘(x-3)(x-1),得x(x-1)=(x+1)(x-3),x^2-x=x^2-2x-3,2x-x=-3,x=-3
(6)方程两边同乘(x-2),得x-3+x-2=-3,2x=-3+3+2,2x=2,x=1
(7)方程两边同乘6x(x+1),得6(2x+1)=5x,12x+6=5x,12x-5x=-6,7x=-6,x=-6/7
(8)方程两边同乘2(3x-1),得3(3x-1)-2=5,9x-3-2=5,9x=5+3+2,9x=10,x=10/9