\(\Leftrightarrow x\left(x^4-9\right)=0\\ \Leftrightarrow x\left(x^2-3\right)\left(x^2+3\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x=0\\x^2=3\\x^2=-3\left(vô.lí\right)\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\\x=\sqrt{3}\\x=-\sqrt{3}\end{matrix}\right.\)
Tìm x:(x-4)²-9x²=0 5(x+3)-2x²-6x=0
b2 tìm x
a)x^2-4x-5=0
b)5x^2-9x-2=0
c)(x^2+1)-5(x^2+1)+6=0
d)(x^2+6x)-2(x+3)^2-17=0
Bài 4: Tìm x:
1) x2 - 9x = 0 2) x(x - 4) – x2 = 7 3) 3x + 2(x – 5) = 5
4) 25x2 - 1 = 0 5) 3x(x - 2) - 5(x - 2) = 0 6) 3x(x - 7) + 4(x – 7) = 0
7) 4x2 – 9 = 0 8) 10x(x - 4) + 2x - 8 = 0 9) x(2x - 5) - 2x2 = 0
10) 2x2 – 4x = 0 11) 2x(3 - 4x) + 3(4x - 3) = 0 12) 2x (x – 5) – 2x2 = 3
mọi người giúp mình vs chiều 1g mình thi rồi! cảm ơn!
Tìm x:
a)2x.(x-5)=2x2+x-11
b)x3-6x2+9x=0
c)x.(x-2018)-2017x+2017.2018=0
Tìm x ,biết:
a, 9x^2 -6x -3=0
b, x^3 + 9x^2 +27x +19=0
c, x(x-5) (x+5) -(x+2) (x^2 -2x +4 )=3
giúp mình vs nhé!
Tìm x
a) (2x - 3)(x^2 + 2) - 2(x + 1)^3 - 9x^2 = -5
b) 3(x - 2) - x^2 + 4 = 0
c) x^3 - 5x^2 - 10x= -50
d) x^3 + 9x= 6x^2
e) 2x^2 - 5x + 3 = 0
f) x^2 - x - 2= 0
tìm x biết
1, x mũ 3 + 4x mũ 2 + 4x = 0
2, ( x + 3 ) mũ 2 - 4 = 0
3, x mũ 4 - 9x mũ 2 = 0
4, x mũ 2 - 6x + 9 = 81
5, x mũ 3 + 6x mũ 2 + 9x - 4x = 0
bài 1:chứng minh rằng với mọi x ta có:
a)-x^2+4x-5<0
b)x^4+3x^2+3>0
c)(x^2+2x+3)(x^2+2x+4)+3>0
bài 2:tìm x:
a)9x^2-6x-3=0
b)x^3+9x^2+27x+19=0
c)x(x-5)(x+5)-(x+2)(x^2-2x+4)=3
