A) X2 – 4X + 4 = 25 X − 171990 + X−211986 + X+11004 =4B) C) 4X – 12

Bài 1(3 điểm): Tỡm x biết:

a) x

2

– 4x + 4 = 25

x − 17

1990 + x−21

1986 + x+1

1004 =4

b)

c) 4

x

– 12.2

x

+ 32 = 0

1

y + 1

z = 0

x + 1

.