Tìm x , biết:1/2+2/3x = 1/4
giup e vs a
Phân tích đa thức sau thành nhân tử
a, \(2^3\)+ 4\(^2\)+6x
b,x\(^2\)-4
c,x\(^2\)-10+25
d,x\(^3\)-4
e,x\(^2\)+xy-3x-3y
g,x\(^2\)-y\(^2\)-4x+4
Giup mk vs ạ bạn nào nhanh mk sẽ vote ạ
Đề bạn có mấy chỗ thiếu mk bổ sung nha
\(a,2^3+4^2+6x=8+16+6x=6x+24=x\left(x+4\right)\\ b,x^2-4=\left(x-2\right)\left(x+2\right)\\ c,x^2-10x+25=\left(x-5\right)^2\\ d,x^3-4x=x\left(x^2-4\right)=x\left(x-2\right)\left(x+2\right)\\ e,x^2+xy-3x-3y=x\left(x+y\right)-3\left(x+y\right)=\left(x-3\right)\left(x+y\right)\\ g,x^2-y^2-4x+4=\left(x-2\right)^2-y^2=\left(x-y-2\right)\left(x+y-2\right)\)
Tick plzz
a: Ta có: \(2x^3+4x^2+6x\)
\(=2x\left(x^2+2x+3\right)\)
b: \(x^2-4=\left(x-2\right)\left(x+2\right)\)
c: \(x^2-10x+25=\left(x-5\right)^2\)
d: \(x^3-4x=x\left(x-2\right)\left(x+2\right)\)
e: \(x^2+xy-3x-3y\)
\(=x\left(x+y\right)-3\left(x+y\right)\)
\(=\left(x+y\right)\left(x-3\right)\)
g: \(x^2-4x+4-y^2\)
\(=\left(x-2\right)^2-y^2\)
\(=\left(x-y-2\right)\left(x+y-2\right)\)
TÌM xEQ biết
a) |x^2 - 3x|=0
b) |4x - 4|=4x-4
c) |2x - 3|=3x - 2
d) |5x - 1|=|3 - 2x|
e) x+1| + |x-3|=3
Ai bít thì giúp vs ^^!
a, |x^2 - 3x| = 0
=> x^2 - 3x = 0
=> x(x - 3) = 0
=> x = 0 hoặc x - 3 = 0
=> x = 0 hoặc x = 3
vậy_
\(\left|a^2-3a\right|=0\)
\(\Rightarrow a^2-3a=0\)
\(\Rightarrow a\left(a-3\right)=0\)
\(\Rightarrow\hept{\begin{cases}a=0\\a=3\end{cases}}\)
Trả lời
Vì lx2-3xl=0
Nên x2-3x=0
=>x(x-3)=0
x=0. x-3=0
x=3
Học tốt
Tìm số tự nhiên x biết:
(x+2)-2=0
(x+3)+1=7
(3x-4)+4=12
(5x+4)-1=13
(4x-8)-3=5
8-(2x-4)=2
7+(5x+2)=14
5-(3x-11)=1
Giúp e vs ạ(Vui lòng trình bày ạ)
\(\left(x+2\right)-2=0\)
\(\Rightarrow x+2-2=0\)
\(\Rightarrow x=0\)
\(\left(x+3\right)+1=7\)
\(\Rightarrow x+3+1=7\)
\(\Rightarrow x+4=7\)
\(\Rightarrow x=3\)
\(\left(3x-4\right)+4=12\)
\(\Rightarrow3x-4+4=12\)
\(\Rightarrow3x=12\)
\(\Rightarrow x=4\)
\(\left(5x+4\right)-1=13\)
\(\Rightarrow5x+4-1=13\)
\(\Rightarrow5x+3=13\)
\(\Rightarrow5x=10\)
\(\Rightarrow x=2\)
\(\left(4x-8\right)-3=5\)
\(\Rightarrow4x-8-3=5\)
\(\Rightarrow4x-11=5\)
\(\Rightarrow4x=16\)
\(\Rightarrow x=4\)
\(8-\left(2x+4\right)=2\)
\(\Rightarrow8-2x-4=2\)
\(\Rightarrow4-2x=2\)
\(\Rightarrow2x=2\)
\(\Rightarrow x=1\)
\(7+\left(5x+2\right)=14\)
\(\Rightarrow7+5x+2=14\)
\(\Rightarrow9+5x=14\)
\(\Rightarrow5x=5\)
\(\Rightarrow x=1\)
\(5-\left(3x-11\right)=1\)
\(\Rightarrow5-3x+11=1\)
\(\Rightarrow16-3x=1\)
\(\Rightarrow3x=15\)
\(\Rightarrow x=5\)
Tìm x, biết:
a) (2x+2)(x-1)-(x+2)(2x+1)=0;
b)(3x+1)(2x-3)-6x(x+2)=16;
c)(12x-5)(4x-1)+(3x-7)(1-16x)=81
mn ơi giúp mik vs ạ :<
a: =>2x^2-2x+2x-2-2x^2-x-4x-2=0
=>-5x-4=0
=>x=-4/5
b: =>6x^2-9x+2x-3-6x^2-12x=16
=>-19x=19
=>x=-1
c: =>48x^2-12x-20x+5+3x-48x^2-7+112x=81
=>83x=83
=>x=1
1,tìm x biết
b,3x chia hết cho x+1
c, (x^2-3x-5) chia hết cho (x-3)
d,(5x+2) chia hết cho x+1
e,(2x^2+3x+2) chia hết cho (x+1)
2,
A=1+(1/2)^2+(1/2)^3+(1/2)^4+(1/2)^5
a, tính 2A
b, chứng minh rằng A= -(1/2)^5+2
giúp mk vs mai phải nộp rùi
ai nhanh mk sẽ cho 5 tk
nhanh lên nha!!!!
1/ a) \(x^2-x-1⋮x-1\)
=>\(x.\left(x-1\right)-1⋮x-1\)
=>\(-1⋮x-1\)(vì x.(x-1)\(⋮\)x-1)
=>x-1\(\inƯ\left(-1\right)\)
Đến đay tự làm
b/c/d/e/ tương tự
Phân tích đa thức
a, x\(^2\)-4x+5
b, (x\(^2\)+3x+1)(x\(^2\)+3x+2)-6
Giúp e vs e đang cần gấp ạ
\(a,Đề.sai\\ b,=\left(x^2+3x+1\right)^2+\left(x^2+3x+1\right)-6\\ =\left(x^2+3x+1-2\right)\left(x^2+3x+1+3\right)\\ =\left(x^2+3x-1\right)\left(x^2+3x+4\right)\)
Bai 1 TINH
a) x ^2 . x -2x^3
b) 6 x^2y . 3xy - 2y^2.x +y
C) 4x^2 +5x -1 .2x^3 -3x
d)-8x^3y + 2y^4 . 3xy^3 - 2x^4 +7y^4
GIUP MINH NHÀ
1.tìm x biết:
a. 3/4 - 2 . |3x+1| = 5/8
b.|3x+2| - |x-3| = 7/2
c |2x+1| + |3x-2| -1/1/3(hỗn sỗ) =0
giúp mik vs
cảm ơn!!
A. 2.\(|3x+1|\)=\(\frac{3}{4}\)-\(\frac{5}{8}\)
2.\(|3x+1|\)=1/8
\(|3x+1|\)=1/8:2
\(|3x+1|\)=1/16
TH1 : 3x+1=1/16
3x=1/16-1
3x=-15/16
x=-15/16:3
x=-5/16
a,\(\frac{3}{4}-2.\left|3x+1\right|=\frac{5}{8}\)
\(\Rightarrow2.\left|3x+1\right|=\frac{3}{4}-\frac{5}{8}=\frac{6}{8}-\frac{5}{8}=\frac{1}{8}\)
\(\Rightarrow\left|3x+1\right|=\frac{1}{8}.\frac{1}{2}=\frac{1}{16}\)
\(\Rightarrow\orbr{\begin{cases}3x+1=\frac{1}{16}\\3x+1=\frac{-1}{16}\end{cases}}\)\(\Rightarrow\orbr{\begin{cases}3x=\frac{1}{16}-1=\frac{-15}{16}\\3x=\frac{-1}{16}-1=\frac{-17}{16}\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x=\frac{-15}{16}.\frac{1}{3}=\frac{-5}{16}\\x=\frac{-17}{16}.\frac{1}{3}=\frac{-17}{48}\end{cases}}\)
Vậy....
b,\(\left|3x+2\right|-\left|x-3\right|=\frac{7}{2}\left(1\right)\)
Ta có bảng xét dấu
x | \(\frac{-2}{3}\) 3 |
3x+2 | - 0 + | + |
x-3 | - | - 0 + |
Nếu x<\(\frac{-2}{3}\) thì \(\left|3x+2\right|-\left|x-3\right|\) \(=-3x-2-3+x\)
\(=-2x-5\)
Từ (1) \(\Rightarrow-2x-5=\frac{7}{2}\)
\(\Rightarrow-2x=\frac{7}{2}+5=\frac{17}{2}\)
\(\Rightarrow x=\frac{17}{2}\cdot\frac{-1}{2}=\frac{-17}{4}\)(thỏa mãn x<\(\frac{-2}{3}\)
Nếu \(\frac{-2}{3}\le x\le3\)thì \(\left|3x+2\right|-\left|x-3\right|=3x+2-\left(3-x\right)\)
\(=3x+2-3+x\)
\(=2x-1\)
Từ (1)\(\Rightarrow\)\(2x-1=\frac{7}{2}\)
\(\Rightarrow2x=\frac{9}{2}\)
\(\Rightarrow x=\frac{9}{4}\)(thỏa mãn......
Còn trưonwfg hợp cuối bạn tự làm nốt nhé
Tìm giá tri nho nhat cua bt:
a) A= 9x^2+8x-5
b)B= 3x^2-x+1
c)C= 2.(2x+1)^2-2.(x-3)^2+1
d)D= (2x^2+4x+5)^2
e)E= x^4+3x^2+2
Huhu, mn giúp mik vs a
Xíu nx mình đi hoc r T_T