\(-x^2-2x-7=0\Leftrightarrow-\left(x^2+2x+1-1\right)-7=0\)
\(\Leftrightarrow-\left(x+1\right)^2-6=0\Leftrightarrow-\left(x+1\right)^2=6\left(voli\right)\)
do \(\left(x+1\right)^2\ge0\Leftrightarrow-\left(x+1\right)^2\le0;6>0\)
\(-x^2-2x-7=0\Leftrightarrow-\left(x^2+2x+1-1\right)-7=0\)
\(\Leftrightarrow-\left(x+1\right)^2-6=0\Leftrightarrow-\left(x+1\right)^2=6\left(voli\right)\)
do \(\left(x+1\right)^2\ge0\Leftrightarrow-\left(x+1\right)^2\le0;6>0\)
Tìm x
(2x-3).(x+1)-2x^2+6x=0
(X^2-x+1).(x-3)-x^3+4x^2=0
(X^2-2).(x^2+2)-x^4-2x+5=0
(X-3).(x^2-3x+2)-(x^2-2x-7).(x-2)+2x^2-2x=0
c)(x-1)^2=4
d)x^3+2x^2-x-2=0
e)(3x+2)^2-(2x-1)^2=0
a) 3x^2-2x-8=0
b)2x^3-3x^2+3x+8 =0
g) ( x+2)^2-(2x-1)^2=(3x+1)^2
h)2x^2-3=0
i)2x^2+x+3=0
Tìm x
1) (2x-1)(x+3)(2-x)=0
2)x^3 + x^2 + x + 1 = 0
3) 2x(x-3)+5(x-3) =0
4)x(2x-7)-(4x-14)=0
5) 2x^3 + 3x^2 + 2x + 3 = 0
a,2x(x-3)+5(x-3)=0
b,(x^2-4)+(x-2)(3-2x)=0
c,x^3-3x^2+3x-1=0
d,x(2x-7)-4x+14=0
e,(2x-5)^2-(x+2)^2=0
f,x^2-x-(3x-3)=0
Giups mình giải bài này nhé?
I) THỰC HIỆN PHÉP TÍNH a) 2x(x^2-4y) b)3x^2(x+3y) c) -1/2x^2(x-3) d) (x+6)(2x-7)+x e) (x-5)(2x+3)+x II phân tích đa thức thành nhân tử a) 6x^2+3xy b) 8x^2-10xy c) 3x(x-1)-y(1-x) d) x^2-2xy+y^2-64 e) 2x^2+3x-5 f) 16x-5x^2-3 g) x^2-5x-6 IIITÌM X BIẾT a)2x+1=0 b) -3x-5=0 c) -6x+7=0 d)(x+6)(2x+1)=0 e)2x^2+7x+3=0 f) (2x-3)(2x+1)=0 g) 2x(x-5)-x(3+2x)=26 h) 5x(x-1)=x-1 IV TÌM GTNN,GTLN. a) tìm giá trị nhỏ nhất x^2-6x+10 2x^2-6x b) tìm giá trị lớn nhất 4x-x^2-5 4x-x^2+3
tìm x: a)x^4-2x^3+5x^2-10x=0
b)(3x+5)^2=(2x-2)^2
. c)x^3–2x^2+x=0
. d)x^2(x-1)-4x^2+8x-4=0
tìm x,biết:
a, 3(x-3)-6x=0
b, 2x(x-15)+2x
c, 2(x-3)+3x=9
d, x(x-11)+2(x-11)=0
e,x(x+2)+8=x^2
f, 8(x+1)+2x=-2
g,12-3(x+2)=0
a.x^2-2x=0
b.(x-1).x-2.(1-x)=0
c.x^3+2x^2+x=0
d.x^3-3x^2=0
a)x2+3x+6=0
b)x2-2x-3=0
c)2x2+7x+3=0
d)x3-2x2-x+2=0
e)x4.(x-1)-2x.(x-3)-9(x-1)=0