a)1/2+4/6+1/12+...+1/(x+1).x=2016/2017
b)5/8/17:x+(-4/17):x+3/1/5:17/1/3=4/11
giải hộ mk nha các bn mk sẽ k mk thề
a,-8/3+7/5+-71/15<x<-13/7+19/14+-7/2
b,-19/6+-15/2+11/3<x<-5/4+19/12+-10/3
c,-6/7+3/35<x<-2/5+3/7
d,x=3/4+1/-12
e,x/14=1/7+-3/14
f,11/18+13/6=85/x
g,8/17+5/17<x/17<6/17+9/17
mong các bn giúp đỡ mk vs mk cần rát gấp
ai nhanh giúp mk thì mk tick cho 3 tick mk thề có lòng tự trọng
ai lm nhanh mk cho 10 tick lun nhanh nha đang cần gấp
các bn lm đến đâu cx dc miễn là lm hộ mk cái ạ, ai đang lm vào nhắn tin vs mk để mk bít nha
a; \(-\dfrac{8}{3}+\dfrac{7}{5}-\dfrac{71}{15}< x< -\dfrac{13}{7}+\dfrac{19}{14}-\dfrac{7}{2}\)
-\(\dfrac{19}{15}\) - \(\dfrac{71}{15}\) < \(x\) < -\(\dfrac{1}{2}\) - \(\dfrac{7}{2}\)
-6 < \(x\) < -4
vì \(x\) \(\in\) Z nên \(x\) = -5
- \(\dfrac{19}{6}+\dfrac{-15}{2}+\dfrac{11}{3}\) < \(x\) < - \(\dfrac{5}{4}\) + \(\dfrac{19}{12}\) - \(\dfrac{10}{3}\)
- \(\dfrac{32}{3}+\dfrac{11}{3}< x< \) \(\dfrac{1}{3}\) - \(\dfrac{10}{3}\)
-7 < \(x\) < - 3
Vì \(x\in\) Z nên \(x\in\) {-6;-5;-4}
a, 1/3 + -2/5 + 1/6 + -1/5 < hoặc bằng x < -3/4 + 2/7 +3/5 +5/7 + -1/4
b, 5/17 + -4/9 +-20/31 + 12/17 + -11/31 < x < hoặc bằng -3/7 + 7/15 + 4/-7 + 8/15 + 2/3
Giúp hộ mk cần gấp! Cảm ơn nha !
\(-\frac{1}{10}< =x< =\frac{3}{5}\)
\(\frac{-4}{9}< x< =\frac{2}{3}\)
Đoàn Thị Thanh Ngân viết lời giải hộ thanks
bn tính từng vế thì thành như thế mà
tìm x biết
a ) x/5 - 7/3 + 3/4 = 17/60
b ) 1/8 - 7/5 - 2/x = (-233)/120
c ) 1/5 + x - 7/3 = 1/2
d ) (-1)/3 - x - 4/5 = 4/15
e ) x : 17/8 = (-2)/5 . (-9)/17
f ) x : 4 = (-5)/2
g ) 5/7: x + 2/5 = 1/5
i ) -12/7 . ( 3/4 - x ) . 5/3 = 0
đâu / có nghĩa là dấu phân số nha
ai nhanh mk tick nha !
Tìm x biết :
a) x* 3/1/4+ ( -7/6 ) * x - 1/2/3 = 5/12
b) 5/8/17 : x + | 2x - 3/4 | = -7/4
c) ( x + 1/2)* ( 2/3 - 2x ) =0
Làm lẹ hộ mk nha! mk cần gấp lắm chìu fai nộp cho thầy rùi. Thanks nhìu.
a) \(x\cdot3\dfrac{1}{4}+\left(-\dfrac{7}{6}\right)\cdot x-1\dfrac{2}{3}=\dfrac{5}{12}\)
\(\Rightarrow\dfrac{3}{4}x-\dfrac{7}{6}x-\dfrac{2}{3}=\dfrac{5}{12}\)
\(\Leftrightarrow9x-14x-8=5\)
\(\Leftrightarrow-5x-8=5\)
\(\Leftrightarrow-5x=5+8\)
\(\Leftrightarrow-5x=13\)
\(\Rightarrow x=-\dfrac{13}{5}\)
Vậy \(x=-\dfrac{13}{5}\)
b) \(5\dfrac{8}{17}:x+\left|2x-\dfrac{3}{4}\right|=-\dfrac{7}{4}\)
\(\Rightarrow5\dfrac{8}{17}:x+\left|2x-\dfrac{3}{4}\right|=-\dfrac{7}{4}\left(đk:x\ne0\right)\)
\(\Leftrightarrow\dfrac{93}{17}\cdot\dfrac{1}{x}+\left|2x-\dfrac{3}{4}\right|=-\dfrac{7}{4}\)
\(\Leftrightarrow\dfrac{93}{17x}+\left|2x-\dfrac{3}{4}\right|=-\dfrac{7}{4}\)
\(\Leftrightarrow\left[{}\begin{matrix}\dfrac{93}{17x}+2x-\dfrac{3}{4}=-\dfrac{7}{4}\left(đk:2x-\dfrac{3}{4}\ge0\right)\\\dfrac{93}{17x}-\left(2x-\dfrac{3}{4}\right)=-\dfrac{7}{4}\left(đk:2x-\dfrac{3}{4}< 0\right)\end{matrix}\right.\)
đến đây bạn giải tiếp nhé
c) \(\left(x+\dfrac{1}{2}\right)\cdot\left(\dfrac{2}{3}-2x\right)=0\)
\(\Rightarrow\left[{}\begin{matrix}x+\dfrac{1}{2}=0\\\dfrac{2}{3}-2x=0\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=0-\dfrac{1}{2}\\2x=0+\dfrac{2}{3}\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{1}{2}\\x=\dfrac{2}{3}:2\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=-\dfrac{1}{2}\\x=\dfrac{1}{3}\end{matrix}\right.\)
Vậy \(x_1=-\dfrac{1}{2};x_2=\dfrac{1}{3}\)
Bài 1 Tìm x,biết
x.3/5=2/3
x.7/17=17/8
3/4 chia x=-7/12
3/8 - 1/6.x=1/4
1/3+1/2 chia x=-4
Bài 2 Tính
-6/11 chia [3/5 . 4/11]
7/12 + 5/12 chia 6 -11/36
[4/5 + 1/2] chia [3/13 - 8/13]
[2/3 - 1/4 + 5/11] chia [5/12 + 1 -7/11]
*Dấu . là dấu nhân nha mn*
Bài 1:
a: \(x=\dfrac{2}{3}:\dfrac{3}{5}=\dfrac{2}{3}\cdot\dfrac{5}{3}=\dfrac{10}{9}\)
b: \(x=\dfrac{17}{8}:\dfrac{7}{17}=\dfrac{17}{8}\cdot\dfrac{17}{7}=\dfrac{289}{56}\)
c: \(x=-\dfrac{3}{4}:\dfrac{7}{12}=\dfrac{-3}{4}\cdot\dfrac{12}{7}=\dfrac{-63}{28}=-\dfrac{9}{4}\)
d: \(\Leftrightarrow x\cdot\dfrac{1}{6}=\dfrac{3}{8}-\dfrac{1}{4}=\dfrac{1}{4}\)
hay \(x=\dfrac{1}{4}:\dfrac{1}{6}=\dfrac{3}{2}\)
e: \(\Leftrightarrow\dfrac{1}{2}:x=-4-\dfrac{1}{3}=-\dfrac{17}{3}\)
hay \(x=-\dfrac{1}{2}:\dfrac{17}{3}=\dfrac{-3}{34}\)
Tính hợp lí ( Giúp mk với )
A = (-4/5 + 4/3) + (-5/4 + 14/5) - 7/3
B = 8/3 x 2/5 x 3/8 x 10 x 19/92
C = -5/7 x 2/11 + (-5)/7 x 9/14 + 1/57
D = 12/19 x 7/15 x (-13)/17 x 19/12 x 17/13
E = 1/1x2 + 1/2x3 + 1/3x4 + ....+ 1/49 x 50
A = ( -4/5 + 4/3 ) + (-5/4 + 14/5) - 7/3
= 8/15 + 31/20 - 7/3
= 25/12 - 7/3
= -1/4
B = 8/3 x 2/5 x 3/8 x 10x 19/92
= 16/15 x 15/4 x 19/92
= 4x19/92
= 19/23
C = - \(\dfrac{5}{7}\) x \(\dfrac{2}{11}\) + \(\dfrac{-5}{7}\) x \(\dfrac{9}{14}\) + \(\dfrac{1}{57}\)
= - \(\dfrac{10}{77}\) - \(\dfrac{45}{98}\) + \(\dfrac{1}{57}\)
= - \(\dfrac{635}{1078}\) + \(\dfrac{1}{57}\)
= - \(\dfrac{36195}{61446}\) + \(\dfrac{1078}{61446}\)
= - \(\dfrac{35117}{61446}\)
D = \(\dfrac{12}{19}\) x \(\dfrac{7}{15}\) x \(\dfrac{-13}{17}\) x \(\dfrac{19}{12}\) x \(\dfrac{17}{13}\)
D = (\(\dfrac{12}{19}\) x \(\dfrac{19}{12}\)) x (- \(\dfrac{13}{17}\) x \(\dfrac{17}{13}\)) x \(\dfrac{7}{15}\)
D = 1 x (- 1) x \(\dfrac{7}{15}\)
D = -1 x \(\dfrac{7}{15}\)
D = - \(\dfrac{7}{15}\)
x.3 1/4+(-7/6).x-1 2/3=5/12
5 8/17:x+(-4/17):x+3 1/7:17 1/3=4/11
-1 5/27-(3x-7/9)^3=-24/27
3(x-1/2)-5(x+3/5)=-x+1/5
Bài 46:
11, - 4|x-2| = -8
12, 5|x+2| = -10(-2)
13, 6|x-2| = 18: (- 3)
14, -7|x+4| = 21 : (-3)
15, 4|x+1| = 8(-2) - 8(-5)
16, 3|x+5| = -9
17, -8|x-3| = 24 - 16: 2
18, -3|x+6| = 6.2 -9
19, 5-|x+7| = 4
20, 12-|x+8| = 10
Giúp mk nha. Mk càn ngay đó
Bài 46:
11: Ta có: \(-4\left|x-2\right|=-8\)
\(\Leftrightarrow\left|x-2\right|=2\)
\(\Leftrightarrow\left[{}\begin{matrix}x-2=2\\x-2=-2\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=4\\x=0\end{matrix}\right.\)
Vậy: x∈{0;4}
12: Ta có: \(5\left|x+2\right|=-10\cdot\left(-2\right)\)
\(\Leftrightarrow5\left|x+2\right|=20\)
\(\Leftrightarrow\left|x+2\right|=4\)
\(\Leftrightarrow\left[{}\begin{matrix}x+2=4\\x+2=-4\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=2\\x=-6\end{matrix}\right.\)
Vậy: x∈{-6;2}
13: Ta có: \(6\left|x-2\right|=18:\left(-3\right)\)
\(\Leftrightarrow6\left|x-2\right|=-6\)(1)
Ta có: \(\left|x-2\right|\ge0\forall x\)
\(\Rightarrow6\left|x-2\right|\ge0\forall x\)(2)
Ta có: -6<0(3)
Từ (1), (2) và (3) suy ra x∈∅
Vậy: x∈∅
14: Ta có:\(-7\left|x+4\right|=21:\left(-3\right)\)
\(\Leftrightarrow-7\left|x+4\right|=-7\)
\(\Leftrightarrow\left|x+4\right|=1\)
\(\Leftrightarrow\left[{}\begin{matrix}x+4=1\\x+4=-1\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-3\\x=-5\end{matrix}\right.\)
Vậy: x∈{-5;-3}
15: Ta có: \(4\left|x+1\right|=8\left(-2\right)-8\left(-5\right)\)
\(\Leftrightarrow4\left|x+1\right|=-16-\left(-40\right)\)
\(\Leftrightarrow4\left|x+1\right|=24\)
\(\Leftrightarrow\left|x+1\right|=6\)
\(\Leftrightarrow\left[{}\begin{matrix}x+1=6\\x+1=-6\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=5\\x=-7\end{matrix}\right.\)
Vậy: x∈{-7;5}
16: Ta có: \(3\left|x+5\right|=-9\)(4)
Ta có: |x+5|≥0∀x
⇒3|x+5|≥0∀x(5)
Ta có: -9<0(6)
Từ (4), (5) và (6) suy ra x∈∅
Vậy: x∈∅
17: Ta có: \(-8\left|x-3\right|=24-16:2\)
\(\Leftrightarrow-8\left|x-3\right|=16\)
\(\Leftrightarrow\left|x-3\right|=-2\)
mà |x-3|≥0>-2∀x
nên x∈∅
Vậy: x∈∅
18: Ta có: \(-3\left|x+6\right|=6\cdot2-9\)
\(\Leftrightarrow-3\left|x+6\right|=3\)
\(\Leftrightarrow\left|x+6\right|=-1\)
mà |x+6|≥0>-1∀x
nên x∈∅
Vậy: x∈∅
19: Ta có: \(5-\left|x+7\right|=4\)
\(\Leftrightarrow\left|x+7\right|=1\)
\(\Leftrightarrow\left[{}\begin{matrix}x+7=-1\\x+7=1\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-8\\x=-6\end{matrix}\right.\)
Vậy: x∈{-8;-6}
20: Ta có: \(12-\left|x+8\right|=10\)
\(\Leftrightarrow\left|x+8\right|=2\)
\(\Leftrightarrow\left[{}\begin{matrix}x+8=2\\x+8=-2\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-6\\x=-10\end{matrix}\right.\)
Vậy: x∈{-10;-6}
( 17 x 12 + 17 x 20 - 17 x 22 ) x ( \(\frac{3}{2}-\frac{4}{6}+\frac{1}{6}\))
Ai tk mk mk tk lại nha
(17 x 12 + 17 x 20 - 17 x 22 ) x ( \(\frac{3}{2}-\frac{4}{6}+\frac{1}{6}\) )
= 17 x ( 12 + 20 - 22 ) x ( \(\frac{9}{6}-\frac{4}{6}+\frac{1}{6}\))
= 17 x 10 x 1
= 170