giúp mik với,tý nữa mik phải nộp b rùi,giúp mik nha
\(A=\frac{5}{6}-\frac{-1}{12}+\frac{2}{3}-\frac{-2}{7}+\frac{1}{25}-\frac{-1}{4}-\frac{5}{42}\)
1. Tìm x thuộc Z biết:
a,\(\frac{-5}{6}.\frac{120}{25}< x< \frac{-7}{15}.\frac{9}{14}\)
b,\(\left(\frac{-5}{3}\right)^3< x< \frac{-24}{35}.\frac{-5}{6}\)
2. Thực hiện phép tính:
a,\(\left(\frac{9}{10}-\frac{15}{16}\right).\left(\frac{5}{12}-\frac{11}{15}-\frac{7}{20}\right)\)
b,\(\frac{-3}{5}+\frac{28}{5}.\left(\frac{43}{56}+\frac{5}{24}-\frac{21}{63}\right)\)
AI GIÚP MIK VỚI,MIK DÂNG CẦN GẤP,SÁNG MAI MIK PHẢI NỘP CHO CÔ RỒI,GIÚP MIK NHA
1)
a)
\(\frac{-5}{6}.\frac{120}{25}< x< \frac{-7}{15}.\frac{9}{14}\)
\(\frac{-1}{1}.\frac{20}{5}< x< \frac{-1}{5}.\frac{3}{2}\)
\(\frac{-20}{5}< x< \frac{-3}{10}\)
\(\frac{-40}{10}< x< \frac{-3}{10}\)
\(\Rightarrow Z\in\left\{-4;-5;-6;-7;-8;-9;-10;...;-39\right\}\)
\(\left(\frac{-5}{3}\right)^3< x< \frac{-24}{35}.\frac{-5}{6}\)
\(\frac{25}{3}< x< \frac{-4}{7}.\frac{1}{1}\)
\(\frac{-25}{3}< x< \frac{-4}{7}\)
\(\frac{-175}{21}< x< \frac{-12}{21}\)
\(\Rightarrow Z\in\left\{-13;-14;-15;-16;...;-174\right\}\)
2)
a)
\(\left(\frac{9}{10}-\frac{15}{16}\right).\left(\frac{5}{12}-\frac{11}{15}-\frac{7}{20}\right)\)
\(=\left(\frac{72}{80}-\frac{75}{80}\right).\left(\frac{25}{60}-\frac{44}{60}-\frac{21}{60}\right)\)
\(=\frac{-3}{80}.\frac{-40}{60}\)
\(=\frac{-1}{-2}.\frac{-1}{-20}\)
\(=\frac{1}{40}\)
Bài 3 Thực hiện phép tính 1 cách hợp lí
\(A=\left(9-\frac{3}{5}+\frac{2}{3}\right)-\left(7+\frac{7}{5}-\frac{3}{2}\right)-\left(3-\frac{9}{5}+\frac{5}{2}\right)\)
giúp mik với 10 phút nữa mik nộp bài rùi
\(A=9-\frac{3}{5}+\frac{2}{3}-7-\frac{7}{5}+\frac{3}{2}-3+\frac{9}{5}-\frac{5}{2}\)
\(=\left(9-7-3\right)+\left(\frac{9}{5}-\frac{7}{5}-\frac{3}{5}\right)+\left(\frac{3}{2}-\frac{5}{2}\right)\)
\(=-2-\frac{1}{5}=-\frac{11}{5}\)
A = 27/12
Hok tốt
cả lời giải nữa nha
Bài 1 : Tính giá trị biểu thức :
a,\(19\frac{5}{8}:\frac{7}{12}-15\frac{1}{4}:\frac{7}{12}\)
b,\(\frac{2}{5}.\frac{1}{3}-\frac{2}{15}:\frac{1}{5}+\frac{3}{5}.\frac{1}{3}\)
(( GIÚP MIK NHA ))
(( GIẢI RA RÙI MIK TICK CHO ))
a)\(19\frac{5}{8}:\frac{7}{12}-15\frac{1}{4}:\frac{7}{12}\)
=(\(19\frac{5}{8}-15\frac{1}{4}\)):\(\frac{7}{12}\)
=(\(19\frac{10}{16}-15\frac{4}{16}\)):\(\frac{7}{12}\)
=\(4\frac{6}{16}:\frac{7}{12}\)
=\(\frac{35}{8}:\frac{7}{12}\)
=\(\frac{35}{8}\cdot\frac{12}{7}\)
=\(\frac{15}{2}\)
b)2/5*1/3-2/15:1/5+3/5*1/3
=2/15-2/3+1/5
=-8/15+1/5
=-1/3
aidi qua dong tinh nho h chom minh nhe
câu 1:thực hiện phép tính (tính nhanh nếu có thể):
a, \(\frac{-7}{25}.\frac{11}{13}+\frac{-7}{25}.\frac{2}{13}-\frac{18}{25}\)
b,\(\frac{5}{7}.\frac{1}{3}-\frac{5}{7}.\frac{1}{4}-\frac{5}{7}.\frac{1}{12}\)
c,\(5\frac{2}{5}.4\frac{2}{7}+5\frac{5}{7}.5\frac{2}{5}\)
d,\(75\%-1\frac{1}{2}+0,5:\frac{5}{12}-\left(\frac{-1}{2}\right)^2\)
câu 2:tìm x biết:
a, \(x+\frac{1}{6}=\frac{-3}{8}\)
b, \(\frac{1}{2}x+\frac{1}{8}x=\frac{3}{4}\)
c,\(2-\left|\frac{3}{4}-x\right|=\frac{7}{12}\)
d,\(\left(2x-4,5\right):\frac{3}{4}-\frac{1}{3}=1\)
GIÚP MIK VS MAI MIK PHẢI NỘP BÀI RỒI!
CACS BN GIÚP MIK TRẢ LỜI TRONG TỐI NAY ĐC K
bài 1 \(\frac{4}{7}+\frac{5}{6}:5-0,375.2\left(-2\right)^2\)
\(\frac{1}{4}+\frac{3}{4}.\left(\frac{-1}{2}+\frac{2}{3}\right)\)
giúp mik nha mai mik kiểm tra rùi
bai 1
\(\frac{7}{4}\)+ \(\frac{5}{6}\):5 - 0,375.2.\(^{\left(-2\right)^2}\)= \(\frac{7}{4}\)+ \(\frac{5}{6}\)x\(\frac{1}{5}\)- \(\frac{15}{4}\). 2.4=\(\frac{7}{4}\)+\(\frac{1}{6}\)-\(\frac{15}{4}\).8=\(\frac{42}{24}\)+\(\frac{4}{24}\)-30=\(\frac{11}{6}\)-30=-169/6
\(\frac{1}{4}\)+\(\frac{3}{4}\). \(\left(\frac{-1}{2}+\frac{2}{3}\right)\)=\(\frac{1}{4}\)+ \(\frac{3}{4}\).\(\left(\frac{-3}{6}+\frac{4}{6}\right)\)= \(\frac{1}{4}+\frac{3}{4}.\frac{1}{6}=\frac{1}{4}+\frac{3}{8}\)= \(\frac{5}{8}\)
Tìm x:
a, x + 30%x = -1,31
b,\(\left(x-\frac{1}{2}\right):\frac{1}{3}+\frac{5}{7}=9\frac{5}{7}\)
c, \(\frac{1}{2}x-\frac{3}{4}=\frac{14}{9}.\frac{3}{7}\)
d,\(\frac{-5}{6}-x=\frac{7}{12}+\frac{-1}{3}\)
e,\(\frac{x+3}{-15}=\frac{1}{3}\)
f,\(\left(4,5-2x\right).\left(-1\frac{4}{7}\right)=\frac{11}{14}\)
GIÚP MIK LM TRONG TỐI NAY NHA, MAI MIK PHẢI NỘP RỒI
\(a)x+30\%x=-1,31\)
\(\Leftrightarrow x+\frac{3x}{10}=-1,31\)
\(\Leftrightarrow10x+3x=-13,1\)
\(\Leftrightarrow13x=-13,1\Leftrightarrow x=-\frac{131}{130}\)
\(b)\left(x-\frac{1}{2}\right):\frac{1}{3}+\frac{5}{7}=9\frac{5}{7}\)
\(\Leftrightarrow\frac{2x-1}{2}.3+\frac{5}{7}=\frac{68}{7}\)
\(\Leftrightarrow\frac{6x-3}{2}=\frac{63}{7}\)
\(\Leftrightarrow\frac{6x-3}{2}=9\)
\(\Leftrightarrow6x-3=18\)
\(\Leftrightarrow x=\frac{7}{2}\)
\(c)\frac{1}{2}x-\frac{3}{4}=\frac{14}{9}.\frac{3}{7}\)
\(\Leftrightarrow\frac{x}{2}-\frac{3}{4}=\frac{2}{3}\)
\(\Leftrightarrow\frac{x}{2}=\frac{17}{12}\)
\(\Leftrightarrow12x=34\Leftrightarrow x=\frac{17}{6}\)
mai mik kiểm tra rùi giúp mik vs pls
a) $\frac{x-1}{x}$ - $\frac{1}{x+1}$ = $\frac{2x-1}{x2+x}$
b) (x+2).(5-3x)=0
c)$\frac{5(1-2x)}{3}$ + $\frac{x}{2}$ = $\frac{3(x-5)}{4}$ - 2
\(\dfrac{x-1}{x}-\dfrac{1}{x+1}=\dfrac{2x-1}{x^2+x}\)
\(\Leftrightarrow\dfrac{x-1}{x}-\dfrac{1}{x+1}=\dfrac{2x-1}{x\left(x+1\right)}\)
ĐKXĐ : \(\left\{{}\begin{matrix}x\ne0\\x+1\ne0\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x\ne0\\x\ne-1\end{matrix}\right.\)
Ta có : `(x-1)/x -1/(x+1) =(2x-1)/(x(x+1))`
\(\Leftrightarrow\dfrac{\left(x-1\right)\left(x+1\right)}{x\left(x+1\right)}-\dfrac{x}{x\left(x+1\right)}=\dfrac{2x-1}{x\left(x+1\right)}\)
`=> x^2 +x -x-1 -x-2x+1=0`
`<=> x^2 -3x =0`
`<=> x(x-3)=0`
\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x-3=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\left(ktm\right)\\x=3\end{matrix}\right.\)
__
`(x+2)(5-3x)=0`
\(\Leftrightarrow\left[{}\begin{matrix}x+2=0\\5-3x=0\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=-2\\3x=5\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=-2\\x=\dfrac{5}{3}\end{matrix}\right.\)
__
\(\dfrac{5\left(1-2x\right)}{3}+\dfrac{x}{2}=\dfrac{3\left(x-5\right)}{4}-2\)
\(\Leftrightarrow\dfrac{20\left(1-2x\right)}{12}+\dfrac{6x}{12}=\dfrac{9\left(x-5\right)}{12}-\dfrac{24}{12}\)
`<=> 2x- 40x + 6x = 9x - 45 -24`
`<=> 2x- 40x + 6x-9x + 45 +24=0`
`<=>-41x+69=0`
`<=>-41x=-69`
`<=> x=69/41`
Cậu tách 2 câu 1 lượt mn trl nhanh hơn đó ạ
a:=>x^2-1-x=2x-1
=>x^2-x-1=2x-1
=>x^2-3x=0
=>x=0(loại) hoặc x=3(nhận)
b:=>x+2=0 hoặc 5-3x=0
=>x=-2 hoặc x=5/3
c:=>20(1-2x)+6x=9(x-5)-24
=>20-40x+6x=9x-45-24
=>-34x+20=9x-69
=>-43x=-89
=>x=89/43
d: =>x^2+4x+4-x^2-2x+3=2x^2+8x-4x-16-3
=>2x^2+4x-19=-2x+7
=>2x^2+6x-26=0
=>x^2+3x-13=0
=>\(x=\dfrac{-3\pm\sqrt{61}}{2}\)
e: =>(2x-3)(2x-3-x-1)=0
=>(2x-3)(x-4)=0
=>x=4 hoặc x=3/2
tính nhanh nha
D=\(\frac{3}{2x4}+\frac{3}{4x6}+...+\frac{3}{98x100}\)
A=\(\frac{1}{2}+\frac{1}{3}+\frac{1}{6}+\frac{1}{12}\)
B=\(6\frac{2}{3}+7\frac{5}{8}+3\frac{1}{3}+4\frac{5}{8}\)
C=[\(4\frac{2}{5}+2\frac{3}{7}\)] - [\(2\frac{2}{5}-1\frac{4}{7}\)]
E=\(\frac{131313}{151515}+\frac{131313}{353535}+\frac{131313}{636363}+\frac{131313}{999999}\)
làm ơn giúp mik nha
mik đang cần gấp
mik sẽ tick(chắc chắn lun) cho người nhanh nhất
1/3xD=1/(2x4)+1/(4x6)+...+1/(98x100)
2/3xD=2/(2x4)+2/(4x6)+...+1/(98x100)
2/3xD= 1/2-1/4+1/4-1/6+...+1/98-1/100
2/3xD=1/2-1/100
2/3xD=49/100
D=147/200
A=1/2+1/3+1/6+1/12
A=(1/2+1/3+1/6)+1/12
A=1+1/12
A=13/12
B=20/3+61/8+10/3+37/8
B=30/3+98/8
B=10+49/4
B=89/4
Giúp mik đi . Ai giúp rùi mà mún ảnh anime hay quotes gì đó thì mik sẽ hậu tạ nha .
Đề : thực hiện phép tính : \(\frac{5}{15}+\frac{14}{25}-\frac{12}{9}+\frac{2}{7}+\frac{11}{25}\)
5/15+14/25-12/9+2/7+11/25=(5/15+2/7)+(14/25+11/25)-12/9=17/35+1-12/9=16/105
=\(\left(\frac{5}{15}-\frac{12}{9}\right)+\left(\frac{14}{25}+\frac{11}{15}\right)+\frac{2}{7}\)
=\(\left(\frac{1}{3}-\frac{4}{3}\right)+1+\frac{2}{7}\)
=\(\frac{-3}{3}+1+\frac{2}{7}=-1+1+\frac{2}{7}\)
=\(\frac{2}{7}\)