tim x biet:a)/x+1/+/3x-1/+/x-1/=3
b)/x-2/+/x-7/=4
tim x nguyen biet:
a 8.(x mu 2 +3).(5-x)
b)(2x + 1)mu 2=25
c) (1-3x)mu3 =64
d)(4-x)mu3 =-27
e) xmu2 -5x =0
b: \(\left(2x+1\right)^2=25\)
=>\(\left[{}\begin{matrix}2x+1=5\\2x+1=-5\end{matrix}\right.\)
=>\(\left[{}\begin{matrix}2x=4\\2x=-6\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=2\\x=-3\end{matrix}\right.\)
c: \(\left(1-3x\right)^3=64\)
=>\(\left(1-3x\right)^3=4^3\)
=>1-3x=4
=>3x=1-4=-3
=>x=-3/3=-1
d: \(\left(4-x\right)^3=-27\)
=>\(\left(4-x\right)^3=\left(-3\right)^3\)
=>4-x=-3
=>x=4+3=7
e: \(x^2-5x=0\)
=>\(x\left(x-5\right)=0\)
=>\(\left[{}\begin{matrix}x=0\\x-5=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\\x=5\end{matrix}\right.\)
tim x,biet:a,x2+3x+1⋮ x-1
b,18x+⋮7
c,4x-5⋮13
a: \(\Leftrightarrow x^2-x+4x-4+5⋮x-1\)
\(\Leftrightarrow x-1\in\left\{1;-1;5;-5\right\}\)
hay \(x\in\left\{2;0;6;-4\right\}\)
c: \(\Leftrightarrow4x-5=13k\left(k\in Z\right)\)
=>4k=13k+5
hay \(x=\dfrac{13k+5}{4}\)
tim x biet:a.2x^2-1=17/8;b.(2x-0,05)(x+3)>0;c.(7-x)(x+19)>0
Cau 3 (2 diem). Tim so tu nhien x, biet:
a. 123 - x =38
b. (x+15) - 7 =33
c. 3x+3 - 13=230
`123-x=38`
`=> x= 123-38`
`=>x=85`
Vậy `x=85`
__
`(x+15) -7=33`
`=>x+15=33+7`
`=>x+16= 40`
`=>x=40-16`
`=>x=24`
Vậy `x=24`
__
`3^(x+3) -13=230`
`=> 3^(x+3) = 230+13`
`=>3^(x+3)=243`
`=> 3^(x+3)=3^5`
`=> x+3=5`
`=>x=5-3`
`=>x=2`
Vậy `x=2`
tim x
a, ( 3-2x ) . ( 1/3 - 1/2 ) ^2 + 4 . (7-5x ) = 9-2x
b, 7 - 3x 1 - 3x
_______ = ______
4 + x x - 5
Sorry bạn nha, mik chỉ làm câu a thôi
bai1.tim x biet:
a,(x+2).(x+3)-(x-2).(x+5)=0
b,(2x+3).(x-4)+(x-5).(x-2)=(3x-5).(x-4)
c,(8x-3).(3x+2)-(4x+7).(x+4)=(2x+1).(5x-1)=33
,(8x-3).(3x+2)-(4x+7).(x+4)=(2x+1).(5x-1)-33 đúng không bạn
Tim cac so nguyen x,y biet:a)*x2 -3*x+1 chia het cho x+2 b)x2-xy = 5x-4y-9 c) (x2-8)*(x2-15)<0 d) (x+1)2+(y+1)2+(x-y)2=2 e) (x2-4)x2>0 ai lam truoc minh tick,mai minh di hoc rui,lam giup minh di pls Thank ban truoc ne ;(
tim x
a)0,25x - 2/3x = -1 1/6
b)3/4 + 1/4.x +x - 7/6 .x = 5/12
\(a,0.25x\) - \(\frac{2}{3}x\) =\(1\frac{1}{6}\)
\(\Rightarrow x\cdot\left(0.25-\frac{2}{3}\right)=1\frac{1}{6}\)
\(\Rightarrow x\cdot\frac{-5}{12}=\frac{7}{6}\)
\(\Rightarrow x=\frac{7}{6}:\frac{-5}{12}\)
\(\Rightarrow x=\frac{-14}{5}=-2.8\)
tim x
a; 4 | 3x - 1 | + | x | - 2 | x-5 | + 7 | x - 3 | = 12
b; 3 |x+4|-|2x+1|-5|x+3|+|x-9|=5