1)Tìm x, biết : \(4.\left[3x-1\right] \left[x\right]-2.\left[x-5\right] 7.\left[x-3\right]=12\) \(\left[2\dfrac{1}{5}-x\right] \left[x-\dfrac{1}{5}\right] 8\dfrac{1}{5}=1,2\) \(3.\left[x 4\right]...

0

AH

ANH HOÀNG

15 tháng 9 2021

tìm x biết:
a) \(5^x.\left(5^3\right)^2=625\)
b)\(\left(\dfrac{12}{15}\right)^x=\left(\dfrac{5}{3}\right)^{-5}-\left(-\dfrac{3}{5}\right)^4\)
c)\(\left(-\dfrac{3}{4}\right)^{3x-1}=\dfrac{256}{81}\)
d)\(172x^2-7^9:98^3=2^{-3}\)

1. \(\dfrac{5\left(x-1\right)+2}{6}-\dfrac{7x-1}{4}=\dfrac{2\left(2x+1\right)}{7}-5\) 2. \(x-\dfrac{3\left(x+30\right)}{15}-24\dfrac{1}{2}=\dfrac{7x}{10}-\dfrac{2\left(10x+2\right)}{5}\) 3. \(14\dfrac{1}{2}-\dfrac{2\left(x+3\right)}{5}=\dfrac{3x}{2}-\dfrac{2\left(x-7\right)}{3}\) 4. \(\dfrac{x+1}{3}+\dfrac{3\left(2x+1\right)}{4}=\dfrac{2x+3\left(x+1\right)}{6}+\dfrac{7+12x}{12}\) 5. \(\dfrac{3\left(2x-1\right)}{4}-\dfrac{3x+1}{10}+1=\dfrac{2\left(3x+2\right)}{5}\) 6....

0

WH

원회으Won Hoe Eu

13 tháng 2 2019

0

TB

Trần Bảo Ngân

26 tháng 11 2023

\(\dfrac{3}{x-5}-\dfrac{x+1}{x\left(x-5\right)}\)

\(\dfrac{8\left(y+2\right)}{3x^2}.\dfrac{15x^5}{4\left(y+2\right)^2}\)

\(\dfrac{8\left(y-1\right)}{3x^2-3}:\dfrac{4\left(y-1\right)^3}{x^2-2x+1}\)

1

Y

YuanShu

26 tháng 11 2023

\(\dfrac{3}{x-5}-\dfrac{x+1}{x\left(x-5\right)}\left(dkxd:x\ne0,x\ne5\right)\\ =\dfrac{3x-x-1}{x\left(x-5\right)}=\dfrac{2x-1}{x^2-5x}\)

----------------------------------------

\(\dfrac{8\left(y+2\right)}{3x^2}.\dfrac{15x^5}{4\left(y+2\right)^2}\left(dkxd:x\ne0,y\ne-2\right)\\ =\dfrac{8}{4}.\dfrac{15x^2.x^3}{3x^2}=10x^3\)

------------------------------------------

\(\dfrac{8\left(y-1\right)}{3x^2-3}:\dfrac{4\left(y-1\right)^3}{x^2-2x+1}\left(dkxd:x\ne1,x\ne-1\right)\\ =\dfrac{8\left(y-1\right)}{3\left(x-1\right)\left(x+1\right)}.\dfrac{\left(x-1\right)^2}{4\left(y-1\right)^3}\\ =\dfrac{2\left(x-1\right)}{3\left(x+1\right)\left(y-1\right)^2}\)

Đúng(2)

HL

Huyen Le

17 tháng 1 2019

Bài 1:cho phương...

1

NL

Nguyễn Lê Phước Thịnh

2 tháng 1 2023

a: \(\Leftrightarrow x^3-3x^2+3x-1-x^3+2x^2-x=5x\left(2-x\right)-11\left(x+2\right)\)

=>-x^2+2x-1=10x-5x^2-11x-22

=>-x^2+2x-1=-5x^2-x-22

=>4x^2+3x+21=0

=>PTVN

b: \(\Leftrightarrow\left(x+10\right)\left(x+4\right)+3\left(x+4\right)\left(x-2\right)=4\left(x+10\right)\left(x-2\right)\)

=>x^2+14x+40+3(x^2+2x-8)=4(x^2+8x-20)

=>x^2+14x+40+3x^2+6x-24=4x^2+32x-80

=>20x+16=32x-80

=>-12x=-96

=>x=8

c: \(\Leftrightarrow6\left(x-3\right)+7\left(x-5\right)=13x+4\)

=>6x-18+7x-35=13x+4

=>-53=4(loại)

d: =>3(2x-1)-5(x-2)=3(x+7)

=>6x-3-5x+10=3x+21

=>3x+21=x+7

=>x=-7

e: =>x^3-6x^2+12x-8-x^3-3x^2-3x-1=-9x^2+1

=>-9x^2+9x-9=-9x^2+1

=>9x=10

=>x=10/9

DP

Dung Phùng

13 tháng 9 2021

tìm x:

\(a,5^x.\left(5^2\right)^3=625\)

\(b,\left(\dfrac{12}{15}\right)^x=\left(\dfrac{5}{4}\right)^{-2}-\left(\dfrac{-3}{5}\right)^4\)

\(c,\left(\dfrac{-3}{4}\right)^{3x-1}=\dfrac{256}{81}\)

\(d,172x^2-7^9:98^3=2^{-3}\)

1

LS

Long Sơn

13 tháng 9 2021

dề bài đâu mà tìm?

DP

Dung Phùng

13 tháng 9 2021

ủa mù à

câu 1 \(\dfrac{3\left(2x+1\right)}{4}\)-\(\dfrac{2\left(3x-1\right)}{5}\)=5câu 2 \(\dfrac{5x-3}{6}\)+5-\(\dfrac{7x-1}{4}\)=\(\dfrac{x+2}{12}\)câu 3 \(\dfrac{\left(x-1\right)\left(x+1\right)}{2}\)+\(\dfrac{3\left(x+1\right)}{4}\)=\(\dfrac{\left(x-2\right)^2}{2}\)câu 4 \(\dfrac{\left(x-4\right)^3}{6}\)+1=\(\dfrac{x\left(x+1\right)}{2}\)-\(\dfrac{\left(x-5\right)\left(x+5\right)}{3}\)câu...

SP

Sửu Phạm

20 tháng 1 2022

1,\(\dfrac{5\left(x-1\right)+2}{6}\)-\(\dfrac{7x-1}{4x}\)=\(\dfrac{2\left(2x+1\right)}{7}\)-52,\(\dfrac{3\left(x-3\right)}{4}\)+\(\dfrac{4x-10,5}{10}\)=\(\dfrac{3 \left(x+1\right)}{5}\)+63,\(\dfrac{2\left(3x+1\right)+1}{4}\)-5=\(\dfrac{2\left(3x-1\right)}{5}\)-\(\dfrac{3x+2}{10}\)Diễn giải ra cho em với ạ!Em cảm...

2

NL

Nguyễn Lê Phước Thịnh

20 tháng 1 2022

Câu 1:

=>15(2x+1)-8(3x-1)=100

=>30x+15-24x+8=100

=>6x+23=100

hay x=77/6

Câu 2:

=>2(5x-3)+12-3(7x-1)=x+2

=>10x-6+12-21x+3-x-2=0

=>-12x=-7

hay x=7/12

Câu 3:

\(\Leftrightarrow2\left(x^2-1\right)+3\left(x+1\right)=2\left(x^2-4x+4\right)\)

\(\Leftrightarrow2x^2-2+3x+3-2x^2+8x-8=0\)

=>11x-7=0

hay x=-7/11

Đúng(1)

HL

Hồ Lê Thiên Đức

20 tháng 1 2022

Câu 4:

(x - 4)^3/6 + 1 = x(x + 1)/2 - (x - 5)(x + 5)/3

<=> (x - 4)^3 + 6/6 = x^2 + x/2 - x^2 - 25/3

<=> (x - 4)^3 + 6/6 = 3x^2 + 3x - 2x^2 + 50/6

<=> (x - 4)^3 + 6 = 3x^2 + 3x - 2x^2 + 50

<=> x^3 - 12x^2 + 48x - 58 = x^2 + 3x + 50

<=> x^3 -13x^2 + 45x - 108 = 0

Đến đây bạn bấm máy nhẩm nghiệm là ra nhé

Câu 5:

3(x + 2)^3/5 - (x - 1)^2/10 = (x - 3)(x + 3)/2

<=> 6(x + 2)^3 - (x - 1)^2/10 = 5(x^2 - 9)/10

<=> 6(x + 2)^3 - (x - 1)^2 = 5(x^2 - 9)

<=> 6x^3 + 36x^2 + 72x + 48 - x^2 + 2x - 1 - 5x^2 + 45 = 0

<=> 6x^3 + 30x^2 + 74x + 92 = 0

Đến đây bạn bấm máy nhẩm nghiệm như câu 4 nhé

Đúng(1)

SN

sói nguyễn

25 tháng 1 2022

1

NH

Nguyễn Huy Tú ( ✎﹏IDΣΛ亗 )

25 tháng 1 2022

1, bạn xem lại đề

2, 15(x-3) + 8x-21 = 12(x+1) +120

<=> 23x - 66 = 12x + 132

<=> 11x = 198 <=> x = 198/11

3, 10(3x+1) + 5 - 100 = 8(3x-1) - 6x - 4

<=> 30x + 10 - 95 = 18x -12

<=> 12x = 73 <=> x = 73/12

Đúng(4)

SN

sói nguyễn

25 tháng 1 2022

Em cảm ơn

NK

Nezuko Kamado

29 tháng 10 2021

Tìm x :

1) \(\left(-0,75x+\dfrac{5}{2}\right).\dfrac{4}{7}-\left(-\dfrac{1}{3}\right)=-\dfrac{5}{6}\)

2) \(\left(4x-9\right)\left(2,5+\dfrac{-7}{3}x\right)=0\)

3) \(\left|x-\dfrac{3}{4}\right|-\dfrac{1}{2}=0\)

4)\(\left(\dfrac{3}{5}-\dfrac{2}{3}x\right)^3=\dfrac{-64}{125}\)

1

NL

Nguyễn Lê Phước Thịnh

29 tháng 10 2021

3: \(\left|x-\dfrac{3}{4}\right|-\dfrac{1}{2}=0\)

\(\Leftrightarrow\left|x-\dfrac{3}{4}\right|=\dfrac{1}{2}\)

\(\Leftrightarrow\left[{}\begin{matrix}x-\dfrac{3}{4}=\dfrac{1}{2}\\x-\dfrac{3}{4}=-\dfrac{1}{2}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{5}{4}\\x=\dfrac{1}{4}\end{matrix}\right.\)

Đúng(2)

KJ

❖ Khang/GD❄ 『ʈєɑɱ❖Hoàng๖ۣۜGia☆』

28 tháng 2 2022

Tìm x biết:

\(a,\left(x-\dfrac{3}{4}\right)+50\%=\dfrac{1}{6}\)

\(b,\dfrac{1}{2}x-\dfrac{5}{6}x=\dfrac{7}{2}\)

\(c,\left(4-x\right)\left(3x+5\right)=0\)

\(d,\dfrac{x}{16}=\dfrac{50}{32}\)

\(e,\left(2x-3\right)+\dfrac{3}{2}=-\dfrac{1}{4}\)

#Toán lớp 6

1

NL

Nguyễn Lê Phước Thịnh

28 tháng 2 2022

a: =>x-3/4=1/6-1/2=1/6-3/6=-2/6=-1/3

=>x=-1/3+3/4=-4/12+9/12=5/12

b: =>x(1/2-5/6)=7/2

=>-1/3x=7/2

hay x=-21/2

c: (4-x)(3x+5)=0

=>4-x=0 hoặc 3x+5=0

=>x=4 hoặc x=-5/3

d: x/16=50/32

=>x/16=25/16

hay x=25

e: =>2x-3=-1/4-3/2=-1/4-6/4=-7/4

=>2x=-7/4+3=5/4

hay x=5/8