|3x-1|-2x=5+3x
ai dung to tk cho
(3x+1)(x+3)=(2-x)(5-3x) ai tra loi nhanh va dung nhat thi to se tick cho ng do nhé
\(\left(3x+1\right)\left(x+3\right)=\left(2-x\right)\left(5-3x\right)\)
\(\Leftrightarrow3x^2+10x+3=10-11x+3x^2\)
\(\Leftrightarrow21x=7\)
\(\Leftrightarrow x=\frac{7}{21}=\frac{1}{3}\)
Vậy : \(x=\frac{1}{3}\)
a. 3(x-1/2) - 5(x+3/5=-x+1/5
b. 2/3× + 1/2x = 5/2:15/4
c. 3x + 2x = 5/8 × 4/3
d. 17/2 - |2x - 3/4| = -7/4
e. (x + 1/25) + 17/25 = 26/25
f. 2/3x - 1/2x = 5/12
g. (x + 1/2) × (2/3-2x) = 0
ai làm nhanh đúng mk cho 10 tk
g. \(\left(x+\frac{1}{2}\right)\left(\frac{2}{3}-2x\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}x+\frac{1}{2}=0\\\frac{2}{3}-2x=0\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=\frac{-1}{2}\\x=\frac{1}{3}\end{cases}}\)
Vậy \(x\in\left\{\frac{-1}{2};\frac{1}{3}\right\}\)
f. \(\frac{2}{3}x-\frac{1}{2}x=\frac{5}{12}\)
\(\Leftrightarrow x\left(\frac{2}{3}-\frac{1}{2}\right)=\frac{5}{12}\)
\(\Leftrightarrow x\left(\frac{4}{6}-\frac{3}{6}\right)=\frac{5}{12}\)
\(\Leftrightarrow\frac{1}{6}x=\frac{5}{12}\)
\(\Leftrightarrow x=\frac{5}{12}\div\frac{1}{6}\)
\(\Leftrightarrow x=\frac{30}{12}=\frac{5}{2}\)
c. \(3x+2x=\frac{5}{8}\times\frac{4}{3}\)
\(\Leftrightarrow x\left(3+2\right)=\frac{5.4}{8.3}\)
\(\Leftrightarrow5x=\frac{5.1}{2.3}\)
\(\Leftrightarrow5x=\frac{5}{6}\)
\(\Leftrightarrow x=\frac{5}{6}\div5\)
\(\Leftrightarrow x=\frac{1}{6}\)
1,tìm x biết
b,3x chia hết cho x+1
c, (x^2-3x-5) chia hết cho (x-3)
d,(5x+2) chia hết cho x+1
e,(2x^2+3x+2) chia hết cho (x+1)
2,
A=1+(1/2)^2+(1/2)^3+(1/2)^4+(1/2)^5
a, tính 2A
b, chứng minh rằng A= -(1/2)^5+2
giúp mk vs mai phải nộp rùi
ai nhanh mk sẽ cho 5 tk
nhanh lên nha!!!!
1/ a) \(x^2-x-1⋮x-1\)
=>\(x.\left(x-1\right)-1⋮x-1\)
=>\(-1⋮x-1\)(vì x.(x-1)\(⋮\)x-1)
=>x-1\(\inƯ\left(-1\right)\)
Đến đay tự làm
b/c/d/e/ tương tự
-3x+2.\([\)45-x - 3(3x+7)-2x\(]\)+4x=-55
Ai nhanh mk tk nha
\(-3x+2.\left[45-x-3\left(3x+7\right)-2x\right]+4x=-55\)
\(-3x+2.\left[45-x-3.3x+7-2x\right]+4=-55\)
\(-3x+2.45-x-6x+7-2x+4x=-55\)
\(-3x+90-x-6x+7-2x+4x=-55\)
\(x.\left(-3+90-6+7-2+4\right)=-55\)
\(x.90=-55\)
\(x=-\frac{11}{18}\)
2/3x - 2/5=1/2x-1/3
1/3x+2/5(x+1)=0
Giups mình với ai xong trc mình tick cho.
(2x-1)^2-(x-3)(2x+5)
x(2x-5)-3(3x-1)^2.x-3x
(3x-1)^3-(2x-1)(4x^2+4x+1)
(1+3x)(1-3x+9x^2)-(2x-1)^3
2(x-3)(x+3)-x(2x-1)(x-3)
ai giúp mình với khó quá:<
Thực hiện phép tính:
a) 3xn (6xn-3 + 1) - 2xn (9x n-3 - 1)
b) 5n+1 - 4 . 5n
Giải giúp mình với ạ! Ai giải nhanh mik tk cho
a,3xn(6xn−3+1)−2xn(9xn−3−1)a,3xn(6xn−3+1)−2xn(9xn−3−1)
=xn[3(6xn−3+1)−2(9xn−3−1)]=xn[3(6xn−3+1)−2(9xn−3−1)]
=xn(18xn−3+3−18xn−3+2)=xn(18xn−3+3−18xn−3+2)
=5xn=5xn
b,5n+1−4.5nb,5n+1−4.5n=5n.5+5n.4=5n(5+4)=45n=5n.5+5n.4=5n(5+4)=45n
c,62.64−43(36−1)c,62.64−43(36−1)
=66−43.36+43=66−43.36+43
=26.36−43.36+43=26.36−43.36+43
=36(26−43)+43=36(26−43)+43
=36[(22)3−43]+43=36.0+43=43=64
~Hok tốt~
TL:
a)
=\(18x^{2n-3}+3x^n-18x^{2n-3}+2x^n\)
=\(6x^n\)
b)
=\(5^n.5-4.5^n\)
=\(5^n\left(5-4\right)\)
=\(5^n\)
vậy.......
hc tốt
\(5^{n+1}-4\cdot5^n\)
\(=5^n\cdot5-4\cdot5^n\)
\(=5^n\cdot\left(5-4\right)\)
\(=5^n\cdot1\)
\(=5^n\)
(3/5 - 2/3x)^3 = -64/125
giúp mk với ai nhanh mk tk cho
\(\left(\frac{3}{5}-\frac{2}{3}x\right)^3=\left(\frac{-4}{5}\right)^3\)
\(\frac{3}{5}-\frac{2}{3}x=\frac{-4}{5}\)
\(\frac{2}{3}x=\frac{7}{5}\)
\(x=\frac{21}{10}\)
\(\left(\frac{3}{5}-\frac{2}{3}.x\right)^3=\frac{-64}{125}\)
\(\Leftrightarrow\left(\frac{3}{5}-\frac{2}{3}.x\right)^3=\left(-\frac{4}{5}\right)^3\)
\(\Rightarrow\frac{3}{5}-\frac{2}{3}.x=-\frac{4}{5}\)
\(\Leftrightarrow\frac{2}{3}.x=\frac{3}{5}-\left(-\frac{4}{5}\right)\)
\(\Leftrightarrow\frac{2}{3}.x=\frac{3}{5}+\frac{4}{5}\)
\(\Leftrightarrow\frac{2}{3}.x=\frac{7}{5}\)
\(\Leftrightarrow x=\frac{7}{5}:\frac{2}{3}\)
\(\Leftrightarrow x=\frac{21}{10}\)
Vậy \(x=\frac{21}{10}\)
(3/5 - 2/3x)^3 = -64/125
giúp mk với ai nhanh mk tk cho
\(\left(\frac{3}{5}-\frac{2}{3}x\right)^3=\frac{-64}{125}\)
\(\left(\frac{3}{5}-\frac{2}{3}x\right)^3=\left(\frac{-4}{5}\right)^3\)
\(\frac{3}{5}-\frac{2}{3}x=\frac{-4}{5}\)
\(\frac{9}{15}-\frac{10x}{15}=\frac{-12}{15}\)
\(-\frac{10x}{15}=\frac{9}{15}-\frac{-12}{15}\)
\(\text{ }-10x=9+12\)
\(-10x=21\)
\(x=\frac{-21}{10}\)
k nha