bài 1: tìm x
a, x + 2 3/4 = 5 2/3 b, x - 1 4/5 = 3 2/7
c, x * 3 1/2 = 4 3/4 d. x : 2 2/ = 4 1/3
Ai làm nhanh mình tik, giải rõ bài trên giúp mình, mình đang cần gấp , cảm ơn
bài 1: tìm x
a) 8/23 . 46/24 = 1/3 . x
b) 1/5 : x = 1/5 - 1/7
c) 4/9 - (x - 1/2) mũ 2 = 1/3
d)3,2 . x - (4/5 + 2/3) : 3 2/3 = 7/10
` 8/23 . 46/24 =1/3 .x`
`=>8/23 . 23/12 =1/3 . x`
`=> 1/3 . x=2/3`
`=>x=2/3 : 1/3`
`=>x=2/3 . 3`
`=> x= 6/3`
`=>x=2`
`----`
`1/5 : x= 1/5-1/7`
`=>1/5 : x= 7/35 - 5/35`
`=> 1/5 :x= 2/35`
`=>x= 1/5 : 2/35`
`=>x=1/5 . 35/2`
`=>x=7/2`
`----`
`4/9 - (x-1/2)^2 =1/3`
`=> (x-1/2)^2 =4/9-1/3`
`=> (x-1/2)^2 =4/9- 3/9`
`=> (x-1/2)^2 =1/9`
`=> (x-1/2)^2 = (+- 1/3)^2`
`@ TH1`
`x-1/2=1/3`
`=>x=1/3+1/2`
`=>x= 2/6 + 3/6`
``=>x= 5/6`
`@ TH2`
`x-1/2=-1/3`
`=>x=-1/3 +1/2`
`=>x= -2/6 + 3/6`
`=>x=1/6`
`----`
`3,2 . x-(4/5+2/3) : 3 2/3 = 7/10`
`=> 3,2 . x-22/15 : 11/3 = 7/10`
`=> 3,2 . x-22/15 = 7/10 . 11/3`
`=> 3,2 . x-22/15 =77/30`
`=> 3,2 .x= 77/30 + 22/15`
`=> 3,2 .x=121/30`
`=>x= 121/30. 5/16`
`=>x= 121/96`
Bài 1: Làm tính nhân
a) -3x^2 . ( 2x^3 - 2x + 1/3 )
b) ( x^4 + 2x^3 - 2/3 ) . ( -3x^4 )
c) ( x + 3 ) . ( x - 4 )
d) ( x - 4 ) . ( x^2 + 4x + 16 )
e) 4. ( x - 1/2 ) . ( x + 1/2 ) . ( 4x^2 + 1 )
Bài 2: Tìm x, biết
a) ( 2 - x ) . (x^2 + 2x + 4 ) + x . ( x - 3 ) . ( x + 4 ) - x^2 + 24 = 0
b) (x/2 + 3 ) . ( 5 - 6x ) + ( 12x - 2 ) . ( x/4 + 3 ) = 0
Bài 1: Làm tính nhân
a) -3x^2 . ( 2x^3 - 2x + 1/3 )
b) ( x^4 + 2x^3 - 2/3 ) . ( -3x^4 )
c) ( x + 3 ) . ( x - 4 )
d) ( x - 4 ) . ( x^2 + 4x + 16 )
e) 4. ( x - 1/2 ) . ( x + 1/2 ) . ( 4x^2 + 1 )
Bài 2: Tìm x, biết
a) ( 2 - x ) . (x^2 + 2x + 4 ) + x . ( x - 3 ) . ( x + 4 ) - x^2 + 24 = 0
b) (x/2 + 3 ) . ( 5 - 6x ) + ( 12x - 2 ) . ( x/4 + 3 ) = 0
1a) -3x2(2x3 - 2x + 1/3) = -6x5 + 6x3 - x2
b) (x4 + 2x3 - 2/3).(-3x4) = -3x8 - 6x7 + 2x4
c) (x + 3)(x - 4) = x2 - 4x + 3x - 12 = x2 - x - 12
d)(x - 4)(x2 + 4x + 16) = (x - 4)(x2 + 4x + 42) = x3 - 64
e) 4(x - 1/2)(x + 1/2)(4x2 + 1) =4(x2 - 1/4)(4x2 + 1) = 4(4x4 + x2 - x2 - 1/4) = 4(4x4 - 1/4) = 16x4 - 1
B2. a) (2 - x)(x2 + 2x + 4) + x(x - 3)(x + 4) - x2 + 24 = 0
=> 8 - x3 + x(x2 + 4x - 3x - 12) - x2 + 24 = 0
=> 8 - x3 + x3 + x2 - 12x - x2 + 24 = 0
=> -12x + 32 = 0
=> -12x = -32
=> x = -32 : (-12) = 8/3
b) (x/2 + 3)(5 - 6x) + (12x - 2)(x/4 + 3) = 0
=> 5x/2 - 3x2 + 15 - 18x + 3x2 + 36x - x/2 - 6 = 0
=> 20x + 9 = 0
=> 20x = -9
=> x = -9/20
Tìm x
a, \(\dfrac{x+5}{4}-\dfrac{x}{2}+1=0\)
b, \(3\left(x+2\right)=\dfrac{x-4}{3}\)
a) \(\dfrac{x+5}{4}-\dfrac{x}{2}+1=0\)
<=> \(\dfrac{x+5-2x+4}{4}=0\)
<=> -x + 9 = 0 <=> x = 9
b) \(3\left(x+2\right)=\dfrac{x-4}{3}\)
<=> 9x + 18 = x-4
<=> 8x = -22
<=> x = \(\dfrac{-11}{4}\)
Bài toán 1: Tìm a biết: 1/5 x 3/a x 4/7= 2x3x4/5x6x7
Bài toán 2: Tìm số tự nhiên a biết:
5/3 < a < 5/7 : 1/3
Bài toán 3: Tìm a biết: 3/4 : 5/6 : 3/a = 9/16
*Tìm X
a, x + 2/5 = 1/2
b, x - 2/5 = 1/7
c,x * 3/4 = 9/20
d, x : 1/7 = 14
e, 2/3 - x = 1/5
f, 4/15 : x = 12/25
*lƯU Ý; VIẾT HẾT CÁC BƯỚC QUY ĐỒNG P/S RA CHO MK NHÉ*
\(a,x+\dfrac{2}{5}=\dfrac{1}{2}\)
\(x=\dfrac{1}{2}-\dfrac{2}{5}\)
\(x=\dfrac{5}{10}-\dfrac{4}{10}\)
\(\Rightarrow x=....\)
\(a,x+\dfrac{2}{5}=\dfrac{1}{2}\\ \Rightarrow x=\dfrac{1}{2}-\dfrac{2}{5}=\dfrac{5-4}{10}=\dfrac{1}{10}\)
\(b,x-\dfrac{2}{5}=\dfrac{1}{7}\\ \Rightarrow x=\dfrac{1}{7}+\dfrac{2}{5}=\dfrac{5+14}{35}=\dfrac{19}{35}\)
\(c,x\cdot\dfrac{3}{4}=\dfrac{9}{20}\\ \Rightarrow x=\dfrac{9}{20}:\dfrac{3}{4}=\dfrac{9}{20}\cdot\dfrac{4}{3}=\dfrac{3\cdot1}{5\cdot1}=\dfrac{3}{5}\)
\(d,x:\dfrac{1}{7}=14\\ \Rightarrow x=14\cdot\dfrac{1}{7}=\dfrac{14}{7}=2\)
\(e,\dfrac{2}{3}-x=\dfrac{1}{5}\\ \Rightarrow x=\dfrac{2}{3}-\dfrac{1}{5}=\dfrac{10-3}{15}=\dfrac{7}{15}\)
\(f,\dfrac{4}{15}:x=\dfrac{12}{25}\\ \Rightarrow x=\dfrac{4}{15}:\dfrac{12}{25}=\dfrac{4}{15}\cdot\dfrac{25}{12}=\dfrac{1\cdot5}{3\cdot3}=\dfrac{5}{9}\)
a, \(x+\dfrac{2}{5}=\dfrac{1}{2}\\ \Rightarrow x=\dfrac{1}{2}-\dfrac{2}{5}\\ \Rightarrow x=\dfrac{5}{10}-\dfrac{4}{10}\\ \Rightarrow x=\dfrac{1}{10}\)
b) \(x-\dfrac{2}{5}=\dfrac{1}{7}\\ \Rightarrow x=\dfrac{1}{7}+\dfrac{2}{5}\\ \Rightarrow x=\dfrac{5}{35}+\dfrac{14}{35}\\ \Rightarrow x=\dfrac{19}{35}\)
c) \(x\times\dfrac{3}{4}=\dfrac{9}{20}\\ \Rightarrow x=\dfrac{9}{20}:\dfrac{3}{4}\\ \Rightarrow x=\dfrac{9}{20}\times\dfrac{4}{3}\\ \Rightarrow x=\dfrac{36}{60}\\ \Rightarrow x=\dfrac{3}{5}\)
Bài 1:Tìm x
A)x-3/4=6.3/8 B)7/8:x=3-1/2
C)x+1/2.1/3=3/ Đ)3/2:4/5-x=2/3
Ê)x.4/3=10/3:17/4 F)x:4/5=5/2
Mình đang cần gấp .Thank you.
Bài 1: tìm đạo hàm của các hàm số sau
1. y=6x2 -\(\dfrac{4}{x}\)+1
2. y=\(\dfrac{2x+1}{-x+1}\)
3. y= \(\sqrt{x^2-3x+4}\)
4. y=\(\dfrac{\left(x^2-1\right)\left(x+3\right)}{x-4}\)
5. y=\(\dfrac{1}{2x^2-3x+5}\)
6. y=(x+1)\(\sqrt{x^2-1}\)
1.
\(y'=12x+\dfrac{4}{x^2}\)
2.
\(y'=\dfrac{3}{\left(-x+1\right)^2}\)
3.
\(y'=\dfrac{2x-3}{2\sqrt{x^2-3x+4}}\)
4.
\(y=\dfrac{x^3+3x^2-x-3}{x-4}\)
\(y'=\dfrac{\left(3x^2+6x-1\right)\left(x-4\right)-\left(x^3+3x^2-x-3\right)}{\left(x-4\right)^2}=\dfrac{2x^3-9x^2-24x+7}{\left(x-4\right)^2}\)
5.
\(y'=-\dfrac{4x-3}{\left(2x^2-3x+5\right)^2}\)
6.
\(y'=\sqrt{x^2-1}+\dfrac{x\left(x+1\right)}{\sqrt{x^2-1}}\)
Các bạn ơi giúp mình mấy bài này với :<
Tìm x:
-3/5 :2x = 3/2 +75%(4 1/2 - 2x) . 3 2/3 = 11/152 1/3x + 4 1/6 = 3 1/7 - 3 1/2x(x - 2/5) : 4/5 = 3x +1/5Ahuhuh giúp mình vớiiii
tìm x
a) X x 3/4 = 1/5 b) 3/7 x X = 2/5 c) 1/3 + 2/9 = 2/12 x X
d) 4/15 x X - 2/3 = 1/5 e) x : 1/7 = 2/3 f) 1/9 : x = 7/3 j) 1/4 + 5/12 = 8/3 : x
h) 7/4 : X - 1/2 = 1/5
a: x*3/4=1/5
=>x=1/5:3/4=1/5*4/3=4/15
b: x*3/7=2/5
=>x=2/5:3/7=2/5*7/3=14/15
c: 1/3+2/9=2/12x
=>1/6x=3/9+2/9=5/9
=>x=5/9*6=30/9=10/3
d: 4/15*x-2/3=1/5
=>4/15*x=2/3+1/5=10/15+3/15=13/15
=>4x=13
=>x=13/4
e: x:1/7=2/3
=>x=2/3*1/7=2/21
f: 1/9:x=7/3
=>x=1/9:7/3=1/9*3/7=3/63=1/21
j: 1/4+5/12=8/3:x
=>8/3:x=3/12+5/12=8/12=2/3
=>x=4
h: =>7/4:x=1/5+1/2=7/10
=>x=7/4:7/10=10/4=5/2