\(a,5x\left(x-2\right)=3x^2-8\\ \Leftrightarrow5x^2-10x-3x^2+8=0\\ \Leftrightarrow2x^2-10x+8=0\\ \Leftrightarrow x^2-5x+4=0\\ \Leftrightarrow\left(x-1\right)\left(x-4\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x=1\\x=4\end{matrix}\right.\)
\(b,x^3>-11x\\ \Leftrightarrow x^3+11x>0\\ \Leftrightarrow x\left(x^2+11\right)>0\\ \Leftrightarrow x>0\left(vì.x^2+11>0\right)\)
giúp mình nhe :>
A)3x^2-x(3x-5)=9
B)5x^2+9x-2=0
C)x/x+5-x-2/x=2x-1/x^2+5x
D)4(5-3x)=5x-5
E)2x^2-11x+14=0
F)3/2x+3-5/x(2x+3)=4/x
Phân tích đa thức thành nhân tử
a) x^3+5x^2+3x-9
b)x^3+6x^2+11x+6
c)x^3+5x^2-3x-15
d)3x^3-4x^2+12x-16
e)2x^4-9x^2-5
Rút gọn
a. ( x2-2x+2) (x-2) ( x2+2x+2) (x+2)
b. (x+1)3 + (x-1)3+ x3-3x(x+1) (x-1)
c. 3(22+1) ( 24 +1)+.......(264+1)+1
d. (5x-2)2+ (2-7x)2 + 2 (2-7x) (5x-2)
e. (11x+32+2) (11x+3) (11x-6) + (6-11x)
Giải các phương trình sau: a) 5x+9 = 2x b) (x+1).(4x-3)= (2x+5)(x+1) c) x/x-2 +x/x+2 = 4x/ x²-4 d) 11x-9= 5x+3 e) (2x+3)(3x-4) =0
Giải phương trình:
a) (x+4)(x+7)(x2+11x+12) = 36(x2+11x+31)
b) (x2+3x-4)3+(2x2- 5x+3) = (3x2 - 2x- 1)3
c) (x+2)/(x+3) - (x+1)/(x-1) = 4/[(x-1)(x+3)]
1)x^4 + 5x^3 - 12x^2 + 5x+1
2) (x-3)(x-5)(x-6)(x-10)- 24x^2
3) 2x^3 + 11x^2 + 3x - 36
Tìm x, biết:
1, ( 3x - 1 )( 5x + 2 ) = ( 7x - 4 )( 2x + 3 ) + x2
2, ( 3x + 7 )2 = ( 4x + 1 )( 5x - 4 ) - 11x2
Thực hiện các phép tính sau: a) (x²/x²+3x)+(3/x+3)+(3/x) b) (2/x+2)+(-4/2-x)+(5x+2/4-x²) c) (1/x-y)+(3xy/y³-x³)+(x-y/x²+xy+y²) d) (3-3x/2x)+(3x-1/2x-1)+(11x-5/2x-4x²)
2x3+11x2+3x-26
x3-5x2+2x+8
3x3+5x2-x-2
6x3-7x2+5x-2
