Lời giải:
\(x^3-4x^2+5x+10=0\)
\(\Leftrightarrow x^3+x^2-5x^2-5x+10x+10=0\)
\(\Leftrightarrow x^2(x+1)-5x(x+1)+10(x+1)=0\)
\(\Leftrightarrow (x+1)(x^2-5x+10)=0\)
\(\Rightarrow \left[\begin{matrix} x+1=0\\ x^2-5x+10=0\end{matrix}\right.\Leftrightarrow \Rightarrow \left[\begin{matrix} x=-1\\ (x-\frac{5}{2})^2=\frac{-15}{4}< 0(\text{vô lý-loại})\end{matrix}\right.\)
Vậy PT có nghiệm $x=-1$
1. (4x-10).(24+5x)=0
2 .(2x-5).(3x-2)=0
3. (2x-1).(3x+1)=0
4. x.(\(x\)2-1)=0
5.(5x+3).(\(x^2\)+4).(x-1)=0
6.(x-1).(x+2).(x+3)=0
7.(x-1).(x+5).(-3x+8)=0
Tìm x biết:
4x2 - 6x = 0
b) 4x2 + 4x = -1
c) 5x2 + x = 0
d) x3 - 5x = 4x2
3x(x-2) = x-2
x3 - 16x = 0
1. 6x(x - 10) - 2x+20=0 6. 3x2 - 6x+3=0
2. 3x2(x - 3) + 3(3 - x)=0 7. 4x2 - 10x+2=0
3. x2 - 8x+16=2(x -4) 8. x2 - 12x -18=0
4. x2 - 16 + 7x ( x+4)=0 9. 3x2 - 10x+3=0
5. x2 - 13x - 14=0 10. 5x2 - 10x+10=0
I : Tìm x , y
a) x^2+y^2-2x+4y+5=0
b) 4x^2+y^2-4x-6x+10=0
c) 5x^2-4xy+y^2-4x+4=0
d)2x^2-4xy+4y^2-10x+25=0
help me
Tìm x:
a) (5x -1)2 - (x2 -4x +4) =0
b) (4x-1).(x+3) = x2 -9
c) x3 -3x +2=0
Bài 1: Tìm x
a) ( 2x-1)2 - (x + 3)2 = 0
b) 5x. ( x-3) + 3 - x = 0
c) ( 5x2 + 3x - 2) 2 = ( 4x2 - 3x -2)
d) x3 + 27 + (x+3) . ( x-9) = 0
Tìm x , biết :
1, x3 - 2x2 - 2x = 0
2, 2x3 - 5x2 + 8x - 3 = 0
3, 3x3 - 14x2 + 4x + 3 = 0
4, x3 + 6x2 - 5x = 0
Tìm x:
a) 2x (x-5) -(x2-10x +25)=0
b) x2 - 9 +3x(x+3) = 0
c) x3 - 16x = 0
d) (2x+3)(x-2) - (x2 -4x+4) = 0
e) 9x2 -(x2 -2x +1)=0
f)x3-4x2 -9x +36 = 0
g) 3x - 6 = (x-1).(x-2)
i) (x-2).(x+2) +(2x+1)2 =-5x.(x-3) =5
k) x2 -1 = (x-1).(2x+3)
l) (2x-1)2 +(x+3).(x-3) -5x(x-2)=6
Tìm x, bik
a)\(x^3-x\)=0
b)\(x^3+5x^2+4x+20=0\)
c)\(x^2-25+3\left(x-5\right)^2=0\)
d)2+4\(\sqrt{2x}+4x^2=0\)
