\(6x^2-2\sqrt{3}x+2=0\)
Ta có : \(6x^2-2\sqrt{3}x+2\)
\(=6\left(x^2-\dfrac{1}{3}\sqrt{3}x+\dfrac{1}{3}\right)\)
\(=6\left(x^2-2x.\left(\dfrac{1}{6}\sqrt{3}\right)+\dfrac{1}{12}\right)+\dfrac{3}{2}\)
\(=6\left(x-\dfrac{\sqrt{3}}{6}\right)^2+\dfrac{3}{2}\ge\dfrac{3}{2}\)
\(=>0\ge\dfrac{3}{2}\left(vô.lí\right)\)
Vậy phương trình vô nghiệm .
1 tim x
2x^4-6x^3+x^2+6x-3=0
tìm x biết
a/ x^3-x^2-x+1=0
b/(2x^3-3)^2-(4x^2-9)=0
c/x^4+2x^3-6x-9=0
d/2(x+5)-x^2-5x=0
Tìm x biết
a) (x-1).(x+2).(x+3).(x+6)-28=0
b) (x^2+4x+3).(x^2+6x+8)=0
tìm x biết
a/ x^3-x^2-x+1=0
b/(2x^3-3)^2-(4x^2-9)=0
c/x^4+2x^3-6x-9=0
d/2(x+5)-x^2-5x=0
x^2(x-3)+18-6x=0
Câu 2: tìm x:
c. (x+1)2 - (x+1)(x-2)=0
d.(2x-3)2-(x+5)2=0
f. x3-x2-25x+25=0
h. x3+2x2-x-2=0
i. 2x(x-3)-15+5x=0
Câu 7: ptđtnt
b. 4x2-9y2+6x-9y
f.x2-3x+2
g. x2+9x+18
h. 3x2-5x-2
Câu 8: tìm x
a. 3x2-6x=0
b. x(x-6)+10(6-x)=0
k. x2+4x+3=0
Tim x sao cho :
\(1+6x-6x^2-x^3=0\)
Tìm x, biết:
1) \(x^2-6x=0\)
2) \(2x^3-5x^2-12x=0\)
3) \(\left(x+1\right)\left(x+2\right)-\left(x+2\right)\left(x+3\right)=0\)
Tim x sao cho:
\(1+6x-6x^2-x^3=0\)
