5 .3^x=8.3^9+7.27^3
Tìm x, biết: \(5.3^x=8.3^9+7.27^3\)
Giang ho dai ca viet nham nhé:
\(5.3^x=8.3^9+7.27^3\)
<=> \(5.3^x=8.3^9+7.\left(3^3\right)^3\) <=> \(5.3^x=8.3^9+7.3^9\)
<=> \(5.3^x=15.3^9\) <=> \(3^x=3.3^9=3^{10}\) => x = 10
nhầm chỉnh lại :
\(5.3^x=8.3^9+7.27^3\Rightarrow5.3^x=8.3^9+7.3^9=15.3^9\Rightarrow15.3^{x-1}=15.3^9\Rightarrow3^{x-1}=3^9\Rightarrow x-1=9\Rightarrow x=10\)
Có 5.3^x=8.3^9+7.27^3
=>5.3^x=8.3^9+7.(3^3)^3
=>5.3^x=8.3^9+7.3^9
=>5.3^x=3^9.(8+7)
=>5.3^x=3^9.15
=>3^x=3^9.15:5
=>3^x=3^9.3
=>3^x=3^10
=>x=10
Vậy x=10
1) TÍNH
( 1253 . 75 - 1755 : 5 ) : 20162017
2) TÌM x , y
a) 5.3x = 8.39 + 7.273
b) 2x + 624 = 5y
Phần trong ngoặc.........phân tích cơ số ra thừa số nguyên tố:
\(125^3\cdot7^5-175^5:5=\left(5^3\right)^3\cdot7^5-\left(5^2\cdot7\right)^5:5=5^9\cdot7^5-5^9\cdot7^5=0\)
1) ( 1253 . 75 - 1755 : 5 ) : 20162017 = 0: 2016^2017 = 0
2)
a)5* 3^x = 8*3^9 + 8* 27^3
3^x = 59049
x=10
1) = 0
2) a = 10
b) khó qá bn ạk
mk chẳng hiểu đề lắm
nha bn
Đề:
Tìm số nguyên x, biết:
a) \(\frac{-5}{6}\) + \(\frac{8}{3}+\frac{29}{-6}\) ≤ x ≤ \(\frac{-1}{2}+2+\frac{5}{2}\)
b) \(5.3^x\) = \(8.3^9+7.27^3\)
Câu b
\(5\cdot3^x=8\cdot3^9+7\cdot27^3\)
\(\Leftrightarrow5\cdot3^x=8\cdot3^9+7\cdot\left(3^3\right)^3\)
\(\Leftrightarrow5\cdot3^x=8\cdot3^9+7\cdot^9\)
\(\Leftrightarrow5\cdot3^x=15\cdot3^9\)
\(\Leftrightarrow3^x=3\cdot3^9=3^{10}\)
Vậy \(x=10\)
#kido
5.\(3^x=8.3^1+7.3^9\)
5 . 3x = 8. 31 + 7. ( 31) 8
5 . 3x = (31)8. (7+8)
5 . 3x = 39 . 15
5 . 3x = 295245
3x = 295245 : 5
3x = 59049
3x = 310
9^8:3^2
3^7.27^5.81^3
36^5:18^5
24.5^5+5^2.5^3
125^4:5^8
giải nhanh giúp tớ. cảm on mọi người
`@` `\text {Ans}`
`\downarrow`
`9^8 \div 3^2`
`= (3^2)^8 \div 3^2`
`= 3^16 \div 3^2`
`=`\(3^{16-2}=3^{14}\)
_____
`3^7 * 27^5 * 81^3`
`= 3^7*(3^3)^5 * (3^4)^3`
`= 3^7 * 3^15 * 3^12`
`=`\(3^{7+15+12}\)
`= 3^34`
______
`36^5 \div 18^5`
`= (36 \div 18)^5`
`= 2^5 = 32`
______
`24*5^5 + 5^2*5^3`
`= 24*5^5 + 5^5`
`= 5^5*(24+1)`
`= 5^5 * 25`
`= 5^5*5^2`
`= 5^7`
______
`125^4 \div 5^8`
`= (5^3)^4 \div 5^8`
`= 5^12 \div 5^8`
`= 5^4`
_____
`@` Phép nâng lên lũy thừa: \(\left(a^m\right)^n=a^{m\cdot n}\)
`@` Chia lũy thừa cùng cơ số: \(a^m\div a^n=a^{m-n}\)
`@` Nhân lũy thừa cùng cơ số: \(a^m\cdot a^n=a^{m+n}\)
\(9^8:3^2\)
\(=\left(3^2\right)^8:3^2\)
\(=3^{16}:3^2\)
\(=3^{14}\)
=============
\(3^7\cdot27^5\cdot81^3\)
\(=3^7\cdot\left(3^3\right)^5\cdot\left(3^4\right)^3\)
\(=3^7\cdot3^{15}\cdot3^{12}\)
\(=3^{7+12+15}\)
\(=3^{34}\)
===============
\(36^5:18^5\)
\(=\left(36:18\right)^5\)
\(=2^5\)
\(=32\)
=============
\(24\cdot5^5+5^2\cdot5^3\)
\(=24\cdot5^5+5^5\)
\(=5^5\cdot\left(24+1\right)\)
\(=5^5\cdot25\)
\(=5^5\cdot5^2\)
\(=5^7\)
==============
\(125^4:5^8\)
\(=\left(5^3\right)^4:5^8\)
\(=5^{12}:5^8\)
\(=5^4\)
tìm x
a, 5.3x=8.39+7.273
b, 52x-3-2.52=52.3
c, 6x+6x+1+6x+2=1548
d, (x-32).45=0
e, 2+4+6+8+...+2x=210
so sánh
7150 và 3775
nhanh nhé khoảng 15 phút nữa thôi (mỗi bạn làm 1 ý cũng được)
a. 5x3^x= 8x19683+7x19683
5x3^x=(8+7)x19683
5x3^x=15x19683
5x3^x= 295245
3^x=295245:5
=59049
3^x= 3^10
vậy x=10
d.x-32=0:45
x-32=0
x=0+32
x=32
b) 9^8.3^2
c) 125:5^3
d) 8^5.2^3:2^4
c) 125:5^3
=125:125
=1
mik chỉ làm đc câu c thôi nha
9^11:3^21-(1/3)^8.3^9