a) x2 + 4x -5 = 0
\(\Leftrightarrow\) x2 -x + 5x - 5 = 0
\(\Leftrightarrow\)x ( x -1 ) + 5 ( x -1 ) =0
\(\Leftrightarrow\) ( x+5)(x-1) = 0
\(\Rightarrow\)\(\left\{{}\begin{matrix}x+5=0\\x-1=0\end{matrix}\right.\) \(\Leftrightarrow\left\{{}\begin{matrix}x=-5\\x=1\end{matrix}\right.\)
Bài 1: Tìm x biết a) x^3 - 4x^2 - x + 4= 0 b) x^3 - 3x^2 + 3x + 1=0 c) x^3 + 3x^2 - 4x - 12=0 d) (x-2)^2 - 4x +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
Tìm x, biết:
a) x. (2x - 7) - 4x + 14 = 0
b) x2. (x - 1) - 4x + 4 = 0
c) x + x2 - x3 - x4 = 0
d) 2x3 + 3x2 + 2x + 3 = 0
e) 4x2 - 25 - (2x - 5). (2x + 7) = 0
g) x3 + 27 + (x + 3). (x - 9) = 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) (3x-1)2+(x+3)3-5(2x-3)(x+3)=0
b) x2-4x+4-(x+3)(x-3)=0
c) x2-3x+2=0
Tìm x biết :
a, (x-2).(x2 +2x +7) +2.( x2-4) -5 .(x-2) =0
b, 4x2 -25 -(2x-5) .(2x+7) =0
c, x3 +27 + (x+3) .(x-9)=0
Giúp mk vs 👍👍
Tìm x,biết:
a, x.(x-5)- 4x+20=0
b, x(x+6)-7x-42=0
c, x^3-5x^2+x-5=0
d, x^4-2x^3+10x^2-20x=0
Bài 1) Tìm x, biết:
a) 9(4x+3)2 = 16(3x-5)2
b) (x3 - x2)2 - 4x2 + 8x - 4 = 0
c) x5 + x4 + x3 + x2 + x + 1 =0
