`3x^2-7x+1=0`
`<=>x^2-7/3x+1/3=0`
`<=>x^2-2.x. 7/6+49/36-37/36=0`
`<=>(x-7/6)^2=37/36`
`<=>x=(+-sqrt{37}+7)/6`
Vậy `S={(+-sqrt{37}+7)/6}`
giải các pt sau băng cách đưa về dạng tích:
1) 3x^2-7x+1=0
2) 2^3+5x^2-3x=0
3) x^3-7x+6=0
4) (2x+1)^2=(x-1)^2
\(3x^2-7x+1=0\)
Giải các phương trình sau:
1. a) 7x + 12 = 0 b) 5x – 2 = 0 c) 12 – 6x = 0 d) – 2x + 14 = 0
2. a) 3x + 1 = 7x – 11 b) 2x + x + 12 = 0 c) x – 5 = 3 – x d) 7 – 3x = 9 – x
e) 5 – 3x = 6x + 7 f) 11 – 2x = x – 1 g) 15 – 8x = 9 – 5
3. a) 0,25x + 1,5 = 0 b) 6,36 – 5,2x = 0
7x (3x-1)+21 (3x-1)=0
\(3x^2-7x+8=0\)
Câu 1 giải các phương trình sau
A)7x+12-0
B) -2x+14-0
C) 3x+1=7x-11
D) 2x+x+12=0
E) x-5=3-x
F) 7-3x-9-x
G) 8-3x-6x+7
H) 11-2x=x-1
K) 15-8x-9-5x
L) 3+2x=5+2
\((2x+3)\left(\dfrac{3x+8}{2-7x}+1\right)=(x-5)\left(\dfrac{3x+8}{2-7x}+1\right)\)
\((3x-1)(x^2+2)=(3x-1)(7x-10)\)
7x-21=0
(3x-5)(x+3)=0
