X x 2 x 3 = 1056

X x 6 = 1056

X=1056:6

X=176

X x 2 x 4 =1960

Xx6=1906

x=1906:6

x=953/3

X x 5 + 148 = 1338

Xx5=1338-148

Xx5=1190

X=1190:5

X=238

500 + X x 4 =940

X x4=940-500

Xx4=440

X=440:4

X=110

1.X * 2 * 3 = 1056

X =1056 : 3 : 2

X=176

2.X*2*4=1960

=1960 : 4 :2

=245

3.X * 5 + 148=1338

=(1338 - 148):5

=238

4.500 + X * 4 = 940

500 + X = 940 : 4

500 + X =235

X           =235 - 500

X           = -265

a: \(\Leftrightarrow x^2+5x+6-\left(x^2+3x-10\right)=6\)

\(\Leftrightarrow x^2+5x+6-x^2-3x+10=6\)

=>2x+16=6

=>2x=-10

hay x=-5

b: \(\Leftrightarrow3\left(x-1-4x^2+4x\right)+4\left(3x^2+9x-2x-6\right)=-27\)

\(\Leftrightarrow3\left(-4x^2+5x-1\right)+4\left(3x^2+7x-6\right)=-27\)

\(\Leftrightarrow-12x^2+15x-3+12x^2+28x-24=-27\)

=>43x=0

hay x=0

c: \(\Leftrightarrow5\left(2y^2+4y+3y+6\right)-2\left(5y^2-5y-4y+4\right)=75\)

\(\Leftrightarrow10y^2+35y+30-10y^2+18y-8=75\)

=>53y=53

hay y=1

d: \(\Leftrightarrow6x^2+27x+4x+18-\left(6x^2+x+12x+2\right)=x+1-x+6=7\)

\(\Leftrightarrow6x^2+31x+18-6x^2-13x-2=7\)

=>18x+16=7

=>18x=-9

hay x=-1/2

Bài 2:
a) UCLN( 94;84;180)
94 = 2.47
84 = 2².3.7
180= 2².3.5
=> UCLN (94;84;180)= 2
b) UCLN ( 16;80;176)
16= 2⁴
80= 2⁴.5
176=2⁴.11
=>UCLN ( 16;80;176)= 2⁴=16

`#3107`

b)

`2.3^x = 162`

`\Rightarrow 3^x = 162 \div 2`

`\Rightarrow 3^x = 81`

`\Rightarrow 3^x = 3^4`

`\Rightarrow x = 4`

Vậy, `x = 4`

c)

`(2x - 15)^5 = (2 - 15)^3`

\(\Rightarrow \)`(2x - 15)^5 - (2x - 15)^3 = 0`

\(\Rightarrow \)`(2x - 15)^3 . [ (2x - 15)^2 - 1] = 0`

\(\Rightarrow\left[{}\begin{matrix}\left(2x-15\right)^3=0\\\left(2x-15\right)^2-1=0\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}2x-15=0\\\left(2x-15\right)^2=1\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}2x=15\\\left(2x-15\right)^2=\left(\pm1\right)^2\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=\dfrac{15}{2}\\2x-15=1\\2x-15=-1\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=\dfrac{15}{2}\\2x=16\\2x=-14\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=\dfrac{15}{2}\\x=8\\x=-7\end{matrix}\right.\)

Vậy, `x \in`\(\left\{-7;8;\dfrac{15}{2}\right\}.\)

`d)`

\(3^{x+2}-5.3^x=?\) Bạn ghi tiếp đề nhé!

`e)`

\(7\cdot4^{x-1}+4^{x-1}=23?\)

\(4^{x-1}\cdot\left(7+1\right)=23\\ \Rightarrow4^{x-1}\cdot8=23\\ \Rightarrow4^{x-1}=\dfrac{23}{8}\)

Bạn xem lại đề!

`f)`

\(2\cdot2^{2x}+4^3\cdot4^x=1056\)

\(\Rightarrow2\cdot2^{2x}+\left(2^2\right)^3\cdot\left(2^2\right)^x=1056\\ \Rightarrow2\cdot2^{2x}+2^6\cdot2^{2x}=1056\\ \Rightarrow2^{2x}\cdot\left(2+2^6\right)=1056\\ \Rightarrow2^{2x}\cdot66=1056\\ \Rightarrow2^{2x}=1056\div66\\ \Rightarrow2^{2x}=16\\ \Rightarrow2^{2x}=2^4\\ \Rightarrow2x=4\\ \Rightarrow x=2\)

Vậy, `x = 2`

_____

\(10 -{[(x \div 3+17) \div 10+3.2^4] \div 10}=5\)

\(\Rightarrow\left[\left(x\div3+17\right)\div10+48\right]\div10=10-5\)

\(\Rightarrow\left[\left(x\div3+17\right)\div10+48\right]\div10=5\)

\(\Rightarrow\left(x\div3+17\right)\div10+48=50\)

\(\Rightarrow\left(x\div3+17\right)\div10=2\)

\(\Rightarrow x\div3+17=20\)

\(\Rightarrow x\div3=3\\ \Rightarrow x=9\)

Vậy, `x = 9.`

5 ( năm )

a, <=> (x-5/100) -1 +(x-4/101) -1 +(x-3/102) -1= (x-100/5) -1+(x-101/4) -1 +(x-102/3) -1
<=> (x-105)(1/100 +1/101 +1/102)= (x-105)(1/5+1/4+1/3)
<=> (x-105)(1/100+1/101+1/102-1/5-1/4-1/3)=0
vì 1/100+1/101+1/102-1/5-1/4-1/3 khác 0 <=> x-105=0
<=> x=105

b, 29-x/21 +1+27-x/23 +1+25-x/25 +1+23-x/27 +1+21-x/29 +1=0
<=> 50-x/21 +50-x/23 +50-x/25 +50-x/27 +50-x/29=0
<=> (50-x)(1/21 +1/23 +1/25 +1/27 +1/29)=0
vì 1/21+1/23+1/25+1/27+1/29 lớn hơn 0
nên 50-x=0
<=> x=50

a) |x| + |-5| = |-37|

<=> |x| + 5 = 37

<=> |x| = 37 - 5 = 32

=> x \(\in\) {32 ; -32}

b)|-6| . |x| = |54|

<=> 6 . |x| = 54

|x| = 54 : 6 = 9

=> x \(\in\){9;-9}

a) ( 1 + 3 + 5 + ....+ 97 + 99 ) - 2 x X = 500 

Áp dụng công thức tính dãy số ta có :

\(1+3+5+...+99=\frac{\left[\left(99-1\right):2+1\right].\left(99+1\right)}{2}=50.100:2=50.50=2500\)

=> 2500 - 2X = 500

=> 2X = 2500 - 500 = 2000

=> X = 2000 : 2 = 1000

a) Ta có : 1 + 3 + 5 + ..... + 97 + 99 

Số số hạng trên là :

 ( 99 - 1 ) : 2 + 1 = 50 số hạng :

 Tổng trên là :

 ( 99 - 1 ) x 50 : 2 = 2450 

Thế vào câu a ta được :

 2450 - 2x = 500

=> 2x = 1950

=> x = 975