tìm x thuộc N
(x+15) \(⋮\)(x+5)
(x+10)\(⋮\)x-3
2x +9 \(⋮\)x+2
4x+20 \(⋮\)(x+3)
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a, Ta có :\(-30+\left(25-x\right)=-1\)
\(\Leftrightarrow\left(-30\right)+25-x=-1\)
\(\Leftrightarrow25-x=\left(-1\right)-\left(-30\right)\)
\(\Leftrightarrow25-x=29\\ \Leftrightarrow x=25-29\)
\(\Leftrightarrow x=\left(-4\right)\)
Vậy \(x=-4\)
b,Ta có :\(\left(x+5\right)+\left(x-9\right)=x+2\)
\(\Leftrightarrow x+5+x-9=x+2\)
\(\Leftrightarrow2.x+\left(5-9\right)=x+2\)
\(\Leftrightarrow\) \(2.x+\left(-4\right)=x+2\)
\(\Leftrightarrow2.x-x=4+2\)
\(\Leftrightarrow x=6\)
Vậy \(x=6\)
a: \(\left(2x-3\right)\left(3x^2+1\right)-6x\left(x^2-x+1\right)+3x^2-2x=10\)
\(\Leftrightarrow6x^3+2x-9x^2-3-6x^3+6x^2-6x+3x^2-2x=10\)
\(\Leftrightarrow-6x-3=10\)
=>-6x=13
hay x=-13/6
b: \(\Leftrightarrow3x^2-3x+x-2-3x^2+5x=-8-5x\)
=>3x-2=-5x-8
=>8x=-6
hay x=-3/4
c: \(\Leftrightarrow64x^3-27-64x^3+32x^2-32x^2+x=20\)
=>x-27=20
hay x=47
d) \(3^x+3^{x+4}=738\)
\(3^x+3^x.3^4=738\)
\(3^x.\left(1+3^4\right)=738\)
\(3^x.82=738\)
\(3^x=9\)
\(3^x=3^2\)
\(\Rightarrow x=2\)
Vậy x=2
c) \(x^{20}-32x^{15}=0\)
\(\Leftrightarrow x^{15}.\left(x^5-32\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}x^{15}=0\\x^5-32=0\end{cases}\Leftrightarrow\orbr{\begin{cases}x=0\\x^5=32\end{cases}\Leftrightarrow}\orbr{\begin{cases}x=0\\x=2\end{cases}}}\)
Vậy ...
\(a,2^{x+1}=3^y=12^x\Rightarrow2^{x+1}.3^y=2^{2x}.3y\)
\(\Rightarrow\frac{2^x}{2^{x+1}}=\frac{3^y}{3^x}\Rightarrow2^{2-x-x-1}=3^{y-x}\)
2. 3x-x = -14-18
2x=-32 suy ra x=-2
3. 2x-x = -13-52
x= -65
4, 2x-10 - 3x +12 = - 6 - 45
x = 2+51 suy ra x= 53
5, 30x + 60 - 6x +30 -24 x =100 +x
x = -10
x-14=3x+18
<=> x-14-3x-18=0
<=> -2x-32=0
<=>-2x=32
<=>x=-16
Vậy x=-16
x-13=2x+52
<=> x-13-2x-52=0
<=> -3x-65=0
<=>-3x=65
<=>x=-65/3
Vậy x=-65/3
2.(x-5)-3.(x-4)=(-6)+15.(-3)
<=> x-5-3x+12=-6-45
<=> 7-2x=-51
<=> 2x=58
<=>x=29
Vậy x=29
30.(x+2)-6.(x-5)-24x=100+x
<=> 30x+60-6x+30-24x=100+x
<=> 90=100+x
<=>x=-10
Vậy x=-10
a, ta có \(x+15⋮x+5,x+5⋮x+5\)
=>x+15-(x+5)\(⋮\)x+5
=>\(x+15-x-5⋮x+5\)
=>\(10⋮x+5\)
=>\(x+5\inƯ\left(10\right)\)=> \(x+5\in\left\{\pm1,\pm2,\pm5,\pm10\right\}\)
=>x\(\in\left\{-15,-10,-7,-6,-4,-3,0,5\right\}\)Mà x thuộc N
=> \(x\in\left\{0,5\right\}\)
Phần tiếp theo tương tự nha bn
Ta có 2x+9\(⋮x+2\)
\(x+2⋮x+2\Rightarrow2\left(x+2\right)⋮x+2\)
=> 2x+9-2(x+2)\(⋮x+2\)
=> 2x+9-2x-4\(⋮x+2\)
=>5\(⋮x+2\)
=>\(x+2\inƯ\left(5\right)\Rightarrow x+2\in\left\{\pm1,\pm5\right\}\)
=>\(x\in\left\{-7,-3,-2,3\right\}\)Mà \(x\inℕ\Rightarrow x=3\)
Vậy.........
Phần sau bn lm tương tự nhé
*****Chúc bạn học giỏi*****