\(x^2\left(x-3\right)-6x+18=0\)
\(\Leftrightarrow\left(x-3\right)\left(x+\sqrt{6}\right)\left(x-\sqrt{6}\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=3\\x=-\sqrt{6}\\x=\sqrt{6}\end{matrix}\right.\)
\(x^2\left(x-3\right)-6x+18=0\)
\(\Leftrightarrow\left(x-3\right)\left(x+\sqrt{6}\right)\left(x-\sqrt{6}\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=3\\x=-\sqrt{6}\\x=\sqrt{6}\end{matrix}\right.\)
Phân tích thành nhân tử :
a. x^2 - 4x - 5 = 0
b. 2x^2 - 6x + 4 = 0
c. 5x^2 - x - 18 = 0
d. 2x^3 - 3x^2 + x + 30
đ. 5x^3 - 21x^2 + 11x + 5
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
Tìm x
(2x-3)(x+1)+(4x3-6x2-6x):(-2x)=18
Tìm x
(2x-3)(x+1)+(4x3-6x2-6x):(-2x)=18
Tìm x
(2x-3)(x+1)+(4x3-6x2-6x):(-2x)=18
1 tim x
2x^4-6x^3+x^2+6x-3=0
a) x^3+6x^2+11x+6
b)x^4+3x^3-7x^2+27x-18
c)x^3-8x^2+x+42
d)x^4+5x^3-7x^2-41x-30
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