1.Tim n€n biet:
a)2 mu n=16
b)27=3.3mu n
2.Viet cac tich sau ve dang cac luy thua
a)5.5.5.3.3
b)5.5.5.5.2.2.2
c)a.a.a.b.b.b.b.b
nho cac ban giup minh nhe
1.tim x thuoc N biet:
a)(2x+1)mu 3=125 b)(x-5)mu 4=(x-5)mu 6 c)2 mu x-15=17 d)(7x-11)mu 3=2 mu 5. 5mu 2+200
2.viet cac tich sau hoac thuong duoi dang luy thua cua mot so:
a)2 mu 5 . 8 mu 4 b)25.125 c)25 mu 5:25 mu 7
3.viet cac tich, thuong sau duoi dang luy thua:
a) 2 mu 10:8 mu 3 b)12 mu 7:6 mu 7 c)5 mu 8:25 mu 2
4.tinh gia tri cac bieu thuc sau:
a mu3 . a mu 9 (a mu 5)mu7 (a mu 6)mu 4. a mu 12 4.5 mu 2-2.3 mu 2
Bài 1 :
a) (2x + 1)3 = 125
=> (2x + 1)3 = 53
=> 2x + 1 = 5
=> 2x = 5 - 1
=> 2x = 4
=> x = 2
b) (x - 5)4 = (x - 5)6
Với hai mũ khác nhau , ta chỉ có thể tìm được giá trị biểu thức bằng 1 hoặc 0 (giá trị của chúng bằng nhau)
+) (x - 5)4 = (x - 5)6 = 0
=> (x - 5)4 = 0
=> (x - 5)4 = 04
=> x - 5 = 0 => x = 0 + 5 = 5
+) (x - 5)4 = (x- 5)6 = 1
=> (x - 5)4 = 1
=> (x - 5)4 = 14
=> x - 5 = 1
=> x = 1 + 5
=> x = 6
Bài 4 :
a3 . a9 = a3 + 9 = a12
(a5)7.(a6)4 .a12 = a35 . a24 . a12 = a35 + 24 + 12 = a71
4.52 - 2.32 = 4.25 - 2.9
= 100 - 18
= 82
mong cac ban giup, minh can gap lam,tuy minh trinh bay hoi xau nhung mong cac ban giup
3.viet cac tich, thuong sau duoi dang luy thua:
a) \(\dfrac{2^{10}}{8^3}\)
\(=\dfrac{2^{10}}{\left(2^3\right)^3}\)
\(=\dfrac{2^{10}}{2^9}\)
\(=2^1\)
1) Viet cac so 2 mu 27 va 3 mu 18 duoi dang luy thua co so mu la9
viet cac tich sau duoi dang 1 luy thua
a/ -8 . -3 . +125
b/ 27 . -23 . -7 .+49
A)viet cac so 2^27 va 3^18 duoi dang cac luy rhua co so mu la 9
B)trong hai so 2^27 va 3^18 so nao lon hon
A) 227 = ( 23 )9 = 89 ; 318 = ( 32 )9 = 99
B) Ta có : 8 < 9 => 89 < 99 => 227 < 318
viet cac tich sau duoi dang luy 1 luy thua
82.324=?
273.94.243=?
\(8^2.32^4=\left(2^3\right)^2.\left(2^5\right)^4=2^6.2^{20}=2^{26}\)
273.94.243\(=\left(3^3\right)^3.\left(3^2\right)^4.\left(3.2^3\right)^3=3^9.3^8.3^3.2^9=3^{20}.2^9\)
viet cac so sau duoi dang luy thua cua 1 so:
\(a)-\frac{8}{27}\)
\(b)\frac{81}{625}\)
viet cac tich sau duoi dang luy thua cua 1 so:
\(a)27.81\)
\(b)\frac{2}{5}.\frac{8}{125}.\frac{16}{625}\)
1.
a) \(-\frac{8}{27}=-\left(\frac{2}{3}\right)^3\)
b) \(\frac{81}{625}=\left(\frac{3}{5}\right)^4\)
2.
a) 27.81=2187=37
b) sai đề
Viet cac tich sau duoi dang 1 luy thua
2.2.2.3.3.6^2.3
\(\left(2\cdot2\cdot2\cdot3\cdot3\cdot6\right)^{2\cdot3}\)
\(=432^6\)
hok tốt
2.2.2.3.3.6^2 . 3 = 23 . 32 . 36 . 3
= 23 . 32 . 22 . 32 . 3
= 24 . 35
viet cac bieu thuc sau duoi dang mot luy thua
32x8 mu 5x1024
viet cac so 2mu27 va 3mu18 duoi dang cac luy thua co so mu la 9
\(3^2=9\)
nên \(3^{18}=\left(3^2\right)^9=9^9\)
Đáp số: \(9^9\)