cac ban oi giup minh voi
giai phuong trinh sau:
x\(^4\)+2x\(^3\)+4x\(^2\)+2x+1 bang 0
Cac ban giup minh voi
1) Giai cac phuong trinh
a) 2010.(4x-3)-4x2+3=0
b)( x2-\(\frac{25}{4}\))2= 10x +1
Giup em voi a
Giai cac bat phuong trinh sau va bieu dien tap nghiem cua bat phuong trinh tren truc so:
a. 2(3x-1)-2x<2x-1
b. 4x-8≥3(3x-2)+4-2x
c. 3(x-2)(x+2)<3x²+x
d. (x+4)(5x-1)>5x²+16x+2
a: =>6x-2-2x<2x-1
=>4x-2<2x-1
=>2x-1<0
=>x<1/2
b: =>4x-8>=9x-6+4-2x
=>4x-8>=7x-2
=>-3x>=6
=>x<=-2
c: =>3x^2-12<3x^2+x
=>x>-12
d: =>5x^2-x+20x-4>5x^2+16x+2
=>19x-4>16x+2
=>3x>6
=>x>2
giai cac phuong trinh sau bang cach bien doi chung thanh nhung phuong trinh voi ve trai la mot binh phuong ve phai la mot hang so
a. \(4x^2-12x-7=0\)
b.\(x^2+2\sqrt{3}x-1=0\)
c. \(3x^2-6x+1=0\)
d.\(2x^2-4\sqrt{2}x+2=0\)
a/ \(\left(2x\right)^2-2.2x.3+3^2-16=0\)
\(\Leftrightarrow\left(2x-3\right)^2=16\)
\(\Leftrightarrow\left[{}\begin{matrix}2x-3=4\\2x-3=-4\end{matrix}\right.\) \(\Rightarrow\left[{}\begin{matrix}2x=7\\2x=-1\end{matrix}\right.\) \(\Rightarrow\left[{}\begin{matrix}x=\dfrac{7}{2}\\x=\dfrac{-1}{2}\end{matrix}\right.\)
b/ \(x^2+2\sqrt{3}.x+\left(\sqrt{3}\right)^2-4=0\)
\(\Leftrightarrow\left(x+\sqrt{3}\right)^2=4\)
\(\Leftrightarrow\left[{}\begin{matrix}x+\sqrt{3}=2\\x+\sqrt{3}=-2\end{matrix}\right.\) \(\Rightarrow\left[{}\begin{matrix}x=2-\sqrt{3}\\x=-2-\sqrt{3}\end{matrix}\right.\)
c/ \(3x^2-6x+3-2=0\)
\(\Leftrightarrow3\left(x^2-2x+1\right)=2\)
\(\Leftrightarrow\left(x-1\right)^2=\dfrac{2}{3}\)
\(\Leftrightarrow\left[{}\begin{matrix}x-1=\dfrac{\sqrt{6}}{3}\\x-1=\dfrac{-\sqrt{6}}{3}\end{matrix}\right.\) \(\Rightarrow\left[{}\begin{matrix}x=\dfrac{3+\sqrt{6}}{3}\\x=\dfrac{3-\sqrt{6}}{3}\end{matrix}\right.\)
d/ \(\left(\sqrt{2}x\right)^2-2.2.\left(\sqrt{2}x\right)+2^2-2=0\)
\(\Leftrightarrow\left(\sqrt{2}x-2\right)^2=2\)
\(\Leftrightarrow\left[{}\begin{matrix}\sqrt{2}x-2=\sqrt{2}\\\sqrt{2}x-2=-\sqrt{2}\end{matrix}\right.\) \(\Rightarrow\left[{}\begin{matrix}\sqrt{2}x=2+\sqrt{2}\\\sqrt{2}x=2-\sqrt{2}\end{matrix}\right.\) \(\Rightarrow\left[{}\begin{matrix}x=\sqrt{2}+1\\x=\sqrt{2}-1\end{matrix}\right.\)
giai phuong trinh va he phuong trinh sau:
x2 + 5x -6=0
b{4x+5y=3
{x-3y=5
giai mau giup toi nhe cac ban
giai cac phuong trinh sau
a, (3x-1)(4x-8)=0
b,(x-2)(1-3x)=0
c,(x-3)(x+4)-(x-3)(2x-1)=0
d,(x+1)(x+2)=2x(x+2)
a)(3x-1)(4x-8)=0
⇔3x-1=0 hoặc 4x-8=0
1.3x-1=0⇔3x=1⇔x=1/3
2.4x-8=0⇔4x=8⇔x=2
phương trình có 2 nghiệm:x=1/3 và x=2
b)(x-2)(1-3x)=0
⇔x-2=0 hoặc 1-3x=0
1.x-2=0⇔x=2
2.1-3x=0⇔-3x=1⇔x=-1/3
phương trình có 2 nghiệm:x=2 và x=-1/3
c)(x-3)(x+4)-(x-3)(2x-1)=0
⇔(x+4)(2x-1)=0
⇔x+4=0 hoặc 2x-1=0
1.x+4=0⇔x=-4
2.2x-1=0⇔2x=1⇔x=1/2
phương trình có hai nghiệm:x=-4 và x=1/2
d)(x+1)(x+2)=2x(x+2)
⇔(x+1)(x+2)-2x(x+2)=0
⇔2x(x+1)=0
⇔2x=0 hoặc x+1=0
1.2x=0⇔x=0
2.x+1=0⇔x=-1
phương trình có 2 nghiệm:x=0 và x=-1
bai 1: cho phuong trinh: x2+(a+b).x-2.(a2-ab+b2) =0. CMR: luon co nghiem voi moi ab
cac ban oi giup minh sap di hoc roi.
Denta = (a + b )^2 - 4(-2(a^2 -ab + b^2))
= a^2 + ab+ b^2 +8a^2 -8ab + 8b^2
=9a^2 + 9b^2 - 7ab
=2( 4a^2 - 4ab + b^2 ) + (a^2 + ab + b^2/4) + 27/4
=2(2a - b)^2 + (a + b/2)^2 + 27/4 lớn hơn 0 với mọi a, b
Vậy pt luôn có nghiệm
a
bai 1: cho phuong trinh: x2+(a+b).x-2.(a2-ab+b2) =0. CMR: luon co nghiem voi moi ab
cac ban oi giup minh bai nay kho mong cac ban thu suc
giai va bien luan phuong trinh theo tham so m,n
a) (m2+m-2)x+3m2+m-4=0
b) m(mx+2n2)-m3=n2(x+m)
cac ban giup minh voi, mai minh phai nop r
giai cac phuong trinh
(6x+3)^2=(x-4)^2
x(x+1)(x+2)(x+3)+1=0
giài giup minh nhaza