\(\Leftrightarrow4x^2-x-1=0\)
\(\text{Δ}=\left(-1\right)^2-4\cdot4\cdot\left(-1\right)=1+16=17\)
Do đó: PT có hai nghiệm phân biệt là:
\(\left\{{}\begin{matrix}x_1=\dfrac{1-\sqrt{17}}{8}\\x_2=\dfrac{1+\sqrt{17}}{8}\end{matrix}\right.\)
Tìm x
a) 4x(x + 1) = 8(x + 1)
b) x(x – 1) – 2(1 – x) = 0
c) 5x(x – 2) – (2 – x) = 0
d) 5x(x – 200) – x + 200 = 0
e) x3 + 4x = 0
f) (x + 1) = (x + 1)2
Tìm x : a) x^3 - 1/4x = 0 b) ( 2x - 1 )^2 - ( x + 3 )^2=0 c) x^2(x-3)+12-4x=0
Tìm x
x^2 - 4x = 0
4x^2 - 9 = 0
2x ( x - 3 ) + 5( x - 3 ) = 0
x ( 2x + 9 )- 4x - 18
( 2x - 1 )^2 - ( x + 2 )^2 = 0
A= 1/x+2 - x^3-4x/x^2+4 .(1/x^2+4x+4 +1/4-x^2) a) tìm TXĐ,R/G A b) x=? để A>0;A<0;A=0 GIÚP MIK VS MIK ĐAG CẦN GẤP
1) (x^3 - x^2)- 4x^2 + 8x - 4 = 0
2) 2x^3 - 50x = 0
3) (x + 1) = ( x + 1)(x - 1)
4) ( 3x+1)^2-4(X-3)^2=0
5)(X+3)(X^2-5X+9)-X^3=2X
6) (4X+3)^2-(4X-3)^2-5X-2=0
7)(X-1)^3-(X-3)(X^2+3X+9)-3X(2-X)=5
Tìm x
x^2 - 4x - 12 = 0
4x^2 + 4x - 24 = 0
8x^3 - 12x^2 + 6x - 1 = 0
tìm x biết
a)4x^2+4x-3=0
b)x^4-3x^3-x+3=0
c)x^2(x-1)-4x^2+8x-4=0
tìm x biết
a)4x^2+4x-3=0
b)x^4-3x^3-x+3=0
c)x^2(x-1)-4x^2+8x-4=0
Tìm x biết:
a) \(3x^2-4x=0\). b) \(\left(x+3\right)\left(x-1\right)+2x\left(x+3\right)=0\).
c) \(9x^2+6x+1=0\). d) \(x^2-4x=4\).
4x^2-4x=-1
27x^3+27x^2+9x+1=0
9x^2(x+1)-4(x+1)=0
(x+1)^3-25(x+1)=0
Giúp mình
