1)
设4x^2 = t (t>0)
(t+3)(t+2) = 12
t^2 +5t -6=0
t-1)*(t+6)=0
t = 1, t = -6(舍去)
所以4x^2 = 1
x = 1/2 x = -1/2
2)
5/(x+1) -10/(x+10) = 2/(3x-3)
5(3x+3)(x+10)-10(x+1)(3x-3) = 2(x+1)(x+10)
17x^2 -143x - 160 = 0
(x+1)*(17x-160)=0
x = -1, x = 160/17
经检验敏喊念,x = -1, x = 160/17都是原方程的渗基根
所以原方程的根是x = -1, x = 160/17.
3)
看不清楚桥困
1)(4X^2+3)(4X^2+2)=12
(4X^2+2+1)(4X^2+2)=12
把(4X^2+2)悄知看成一个整体
(4x²+2)²神虚+ (4x²+2)=12
4x²启瞎消+2=3
x=±1/2
2) 无解
3)x=2或1/2 或 x=-3或-1/3