p) -5 \(\times\)( x - 1/5) - 1/2 \(\times\)( x - 2/3 ) = 3/2 \(\times\)x - 5/6
bài nâng cao:
a) 33.x - 1 = 9x - 2
b) ( x - 1)4 = ( x - 3 )6
Các bạn giúp tui nha!!! Vì chiều nay là tui có toàn rùi.
Thank you!!!
Rút gọn biểu thức:
a)3x×(4x-3)-(2x-1)×(6x+5)
b)3x×(x-1)^2-2x×(x+3)×(x-3)+4x×(x-4)
c)(x-1)^3×(x+2)×(x^2x+4)+3×(x+4)×(x-4)
d)(x+1)×(x^2+x+1)×(x-1)×(x^2-x+1)
Giúp mk vs nha. Cảm ơn các bạn nhiều♡♡♡¤¤¤☆☆☆
Việt Nam vô địch..♡♡♡☆☆☆☆☆☆
a: \(=12x^2-9x-12x^2-10x+6x+5=-13x+5\)
b: \(=3x\left(x^2-2x+1\right)-2x\left(x^2-9\right)+4x^2-16x\)
\(=3x^3-6x^2+3x-2x^3+18x+4x^2-16x\)
\(=x^3-2x^2+3x\)
c: \(=x^3-3x^2+3x-1+x^3+8+3\left(x^2-16\right)\)
\(=2x^3-3x^2+3x+7+3x^2-48=2x^3+3x-41\)
d: \(=\left(x^3+1\right)\left(x^3-1\right)=x^6-1\)
Tìm x biết :
a) -2×(x-1/3)-5× (x+1/3)=1/2×x
b) -(1/2×x-3/4)-(-x+1)=-3/2
Cảm ơn nhiều nha!
a) \(-2\left(x-\dfrac{1}{3}\right)-5\left(x+\dfrac{1}{3}\right)=\dfrac{1}{2}x\)
\(\Leftrightarrow-2x+\dfrac{2}{3}-5x-\dfrac{5}{3}=\dfrac{1}{2}x\)
\(\Leftrightarrow-7x-1=\dfrac{1}{2}x\)
\(\Leftrightarrow-7x-\dfrac{1}{2}x=1\)
\(\Leftrightarrow-\dfrac{15}{2}x=1\)
\(\Leftrightarrow x=1:\left(-\dfrac{15}{2}\right)=-\dfrac{2}{15}\)
b) \(-\left(\dfrac{1}{2}x-\dfrac{3}{4}\right)-\left(-x+1\right)=\dfrac{3}{2}\)
\(\Leftrightarrow-\dfrac{1}{2}x+\dfrac{3}{4}+x-1=\dfrac{3}{2}\)
\(\Leftrightarrow\dfrac{1}{2}x-\dfrac{1}{4}=\dfrac{3}{2}\)
\(\Leftrightarrow\dfrac{1}{2}x=\dfrac{3}{2}+\dfrac{1}{4}=\dfrac{7}{4}\)
\(\Leftrightarrow x=\dfrac{7}{4}:\dfrac{1}{2}\)
\(\Leftrightarrow x=\dfrac{7}{2}\)
Tìm x biết
a, | 1/2 × x - 3 | = 1/2
b, | 3× x + 1/5 | - 1/3 = 2/3
c, |3× x - 1/5 | + | 15× x - 1 |= 6/2
d, | 1/2 × x - 3 | < 1/2
e, | 3× x - 4/5 | > 1/3
a: \(\left|\dfrac{1}{2}x-3\right|=\dfrac{1}{2}\)
\(\Leftrightarrow\left[{}\begin{matrix}\dfrac{1}{2}x-3=\dfrac{1}{2}\\\dfrac{1}{2}x-3=-\dfrac{1}{2}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}\dfrac{1}{2}x=\dfrac{7}{2}\\\dfrac{1}{2}x=\dfrac{5}{2}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=7\\x=5\end{matrix}\right.\)
b: \(\left|3x+\dfrac{1}{5}\right|-\dfrac{1}{3}=\dfrac{2}{3}\)
\(\Leftrightarrow\left|3x+\dfrac{1}{5}\right|=1\)
\(\Leftrightarrow\left[{}\begin{matrix}3x+\dfrac{1}{5}=1\\3x+\dfrac{1}{5}=-1\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}3x=\dfrac{4}{5}\\3x=-\dfrac{6}{5}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{4}{15}\\x=-\dfrac{2}{5}\end{matrix}\right.\)
d: \(\left|\dfrac{1}{2}x-3\right|< \dfrac{1}{2}\)
\(\Leftrightarrow\left\{{}\begin{matrix}\dfrac{1}{2}x-3>-\dfrac{1}{2}\\\dfrac{1}{2}x-3< \dfrac{1}{2}\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}\dfrac{1}{2}x>\dfrac{5}{2}\\\dfrac{1}{2}x< \dfrac{7}{2}\end{matrix}\right.\Leftrightarrow5< x< 7\)
e: \(\left|3x-\dfrac{4}{5}\right|>\dfrac{1}{3}\)
\(\Leftrightarrow\left[{}\begin{matrix}3x-\dfrac{4}{5}>\dfrac{1}{3}\\3x-\dfrac{4}{5}< -\dfrac{1}{3}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}3x>\dfrac{17}{15}\\3x< \dfrac{7}{15}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x>\dfrac{17}{45}\\x< \dfrac{7}{45}\end{matrix}\right.\)
I. Giải các phương trình sau
a)x-(x/2-3+x/4)/2 = 2x - (10x-7x/3)/2 - x -1
b) 3/10×(1,2- x)-5+7x/4=1/20×(9x+0,2) - 12,5x+4,5/5
II. Giải các phương trình sau
a) 25x - 655/95-5×(x-12)/209= 89-3x-2(x-18)/5
b)8×(x+22)/45{7x+149+[6×(x+12)/5]}/9 = [x+35+2×(x+50)/9]/5
c) [x+2(3-x)/5]/14- [5x - 4(x-1)]/24 = (7x+2+9-3x/5)/12 + 2/3
III. Giải phương trình sau:
(59-x/41) + (57-x/43) + (55-x/45) + (53-x/47) + (51-x/49)=-5
MỌI NGƯỜI GIÚP MÌNH VỚI Ạ. AI NHANH MÌNH TICK NHA
Tìm x thuộc Z, biết
a, -5/7 + 1 + 30/-7 <_ x <_ -1/6 + 1/3 + 5/6
b, 1/2 - ( 1/3 + 1/4 ) < x < 1/48 - ( 1/16 - 1/6 )
c, ( x - 1/2 ) × ( x +3/4 ) < 0
d, 3/ ( x +2) ×( x +5) + 5/ ( x +5 ) × ( x+ 10) + 7/ ( x +10) ( x +17) = x / ( x+2) × ( x + 17)
a, -5/7+ 1+ 30/-7< x < -1/6+ 1/3 +5/6
<=> -4< x <1
<=> x = -3; -2; -1; 0
a, \(\dfrac{-5}{7}+1+\dfrac{30}{-7}\le x\le\dfrac{-1}{6}+\dfrac{1}{3}+\dfrac{5}{6}\)
<=> -4 \(\le x\le1\)
Do x \(\in Z\Rightarrow x=-4;-3;-2;-1;0;1\)
b, \(\dfrac{1}{2}-\left(\dfrac{1}{3}+\dfrac{1}{4}\right)< x< \dfrac{1}{48}-\left(\dfrac{1}{16}-\dfrac{1}{6}\right)\)
<=> -\(\dfrac{1}{12}< x< \dfrac{1}{8}\)
Do x \(\in Z\Rightarrow x=0;1\)
@Mai Tran
c, Do (x - \(\dfrac{1}{2}\))(x + \(\dfrac{3}{4}\)) < 0
=> x - \(\dfrac{1}{2};x+\dfrac{3}{4}\) khác dấu
Có x - \(\dfrac{1}{2}< x+\dfrac{3}{4}\Rightarrow x-\dfrac{1}{2}< 0;x+\dfrac{3}{4}>0\)
=> \(\left[{}\begin{matrix}x-\dfrac{1}{2}< 0\\x+\dfrac{3}{4}>0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x< \dfrac{1}{2}\\x>-\dfrac{3}{4}\end{matrix}\right.\)<=> -\(\dfrac{3}{4}< x< \dfrac{1}{2}\)
Do x \(\in Z\Rightarrow x=0\)
@Mai Tran
Bài 3 : Tìm x, biết :
a) 16x^2 - (4x - 5)^2 = 15
b) (2x + 3)^2 - 4×(x - 1)×(x+ 1)=49
c) (2x + 1)×(1 - 2x)+(1 - 2x)^2=18
d) 2×(x + 1)^2 - (x - 3)×(x + 3) - (x - 4)^2=0
e) (x -5)^2 - x×(x - 4)=9
f) (x - 5)^2 + (x - 4)×(1 - x)=0
Giúp mình với, mình bó tay bài này rồi ;-;
Bài 3: Tìm x, biết:
a) \(16x^2-\left(4x-5\right)^2=15\)
\(\Leftrightarrow16x^2-16x^2+40x-25-15=0\)
\(\Leftrightarrow40x-40=0\)
\(\Leftrightarrow4x=40\)
\(\Leftrightarrow x=10\)
Vậy x = 10
b) \(\left(2x+3\right)^2-4\left(x-1\right)\left(x+1\right)=49\)
\(\Leftrightarrow\left(2x+3\right)^2-4\left(x^2-1\right)=49\)
\(\Leftrightarrow4x^2+12x+9-4x^2+4-49=0\)
\(\Leftrightarrow12x-36=0\)
\(\Leftrightarrow12x=36\)
\(\Leftrightarrow x=3\)
Vậy x = 3
c) \(\left(2x+1\right)\left(1-2x\right)+\left(1-2x\right)^2=18\)
\(\Leftrightarrow\left(1-2x\right)\left(2x+1+1-2x\right)=18\)
\(\Leftrightarrow2\left(1-2x\right)=18\)
\(\Leftrightarrow2-4x=18\)
\(\Leftrightarrow4x=-16\)
\(\Leftrightarrow x=-4\)
Vậy x =-4
d) \(2\left(x+1\right)^2-\left(x-3\right)\left(x+3\right)-\left(x-4\right)^2=0\)
\(\Leftrightarrow2x^2+4x+2-x^2+9-x^2+8x-16=0\)
\(\Leftrightarrow12x-5=0\)
\(\Leftrightarrow12x=5\)
\(\Leftrightarrow x=\frac{5}{12}\)
Vậy \(x=\frac{5}{12}\)
e) \(\left(x-5\right)^2-x\left(x-4\right)=9\)
\(\Leftrightarrow x^2-10x+25-x^2+4x=9\)
\(\Leftrightarrow25-6x=9\)
\(\Leftrightarrow6x=16\)
\(\Leftrightarrow x=\frac{8}{3}\)
Vậy \(x=\frac{8}{3}\)
f) \(\left(x-5\right)^2+\left(x-4\right)\left(1-x\right)=0\)
\(\Leftrightarrow x^2-10x+25+x-x^2-4+4x=0\)
\(\Leftrightarrow21-5x=0\)
\(\Leftrightarrow5x=21\)
\(\Leftrightarrow x=\frac{21}{5}\)
Vậy \(x=\frac{21}{5}\)
1,1/,1/x2+9x+20+1/x2+11x+30+1/x2+13x+42=1/18
2,(2-x/2018) -1=1-x/2019-x/2020
3,(x+5)2+(x-2)2=2×(x-1)×(x+1)+5
4,(x2-1)2=4x+1
5,x3+(x+1)3+(x+2)3=(x+3)3
Các bạn giúp mình nhé, mình cần gấp. Cảm ơn các bạn!
A. 5x=6×(x-1)
B.1×(3x)=(x+1)×2
C.3×(2x+1)=5×(x+2)
D.5×(7-x)=-4×(8x-2)
A. x^2x - 3 - 2×5^2= 5^2×3
B. 5^x +1 = 125
C . ( 12x _ 4 ^3 ) × 8^3 = 4 × 8 ^4
D. X ^50 = x