Bài 1: tìm x
a, 4x² - 20x + 25 = 49
b, x²(x + 3) + 3 - x =0
c, (x + 2)(x² - 2x + 4) - x(x - 1²) = 2x²
d, (x + 1)³ - (x - 1)³ - 6(x - 1)² = -19
e, (x - 4)² - (x - 2)(x + 2) =6
f, x(x - 3) - 2x + 6=0
k, 2x² + 3x - 5 =0
l, (x - 1)³ -(x + 3)(x² - 3x + 9) + 3(x² - 4) =2
m, x(x + 1) - x² - 2x =5
n, 36x³ - 4x= 0
o, -4x² + x² - 8x + 2 = 0
q, (x² - 4x)² + 7(x² - 4x) + 12 = 0
p, x³ = 1/4x
r, (x² + 9)² - 36x² =0
s, x³ - 2x² - 4x + 8 =0
t, x³ + 9x² - 10x = 0
Bài 5 : tìm x
a, (x² + 4)² - 16x² = 0
b, x³ - 2x² - 9x + 18 =0
c, 9(5 - x) + x² - 10x = -25
d,(x² + 1)² - 6(x² + 1) + 9 = 0 
2
