N=1/6.5/9+5/9.2/7+1/9.5/7-5/9.3/7
Tìm n thuộc Z sao cho:
a)1/9.3^4.3^n=3^7
b)1/2.2^n+4.2^n=9.2^5
a: \(3^n\cdot3^4\cdot\dfrac{1}{9}=3^7\)
\(\Leftrightarrow3^n\cdot3^2=3^7\)
=>n+2=7
hay n=5
b: \(\Leftrightarrow2^n\cdot\left(\dfrac{1}{2}+4\right)=9\cdot2^5\)
\(\Leftrightarrow2^n=9\cdot2^5:\dfrac{9}{2}=9\cdot\dfrac{2}{9}\cdot2^5=2^6\)
hay n=6
-Toán M: 8 15P: 10 6 1T: 7 KTHK: 6.8 -Vật lí M: 8 15P: 6 1T: 5 KTHK: 8 -Sinh học M: 10 15P: 8 1T: 6.5 KTHK: 9 -Ngữ Văn 1T: 7.5 6.5 KTHK: 8.3 -Lịch sử 15P: 10 1T: 8 KTHK: 8.8 -Địa lí 15P: 9 1T: 7 KTHK: 7.5 -Ngoại ngữ M: 7 1T: 6 KTHK: 6 -GDCD 1T: 9 KTHK: 9.5 -Công nghệ 1T: 9.5 KTHK: 9.5 -Tin học M: 10 15P: 9 1T: 10 KTHK: 10 Có Đc Hs giỏi Hk Ạ
A=2^10.3^10-2^10.3^9/2^9.3^10
B=5^11.7^12+7^11.5^11/5^12.7^12+9.5^11.7^11
1/tìm x
(3/5)5.x=(3/5)7x+3/10=5+7/106/7.x=18/231/9.34.3n=371/2.2n+4.2n=9.25giúp mình vs, mình đang cần gấp
1.1
x=(3/5)^7:(3/5)^5=(3/5)^7-5=(3/5)62=6/5=1,2
1.2
x=5+7/10+3/10=5+10/10=5+1=6
1.3
x=\(\frac{18}{23}\) :\(\frac{6}{7}\) =\(\frac{18}{23}\) . \(\frac{7}{6}\) = \(\frac{21}{23}\)
1. Rút gọn:
a. \(\frac{2^{10}.3^{10}-2^{10}.3^9}{2^9.3^{10}}\)
b. \(\frac{5^{11}.7^{12}+5^{11}.7^{11}}{5^{12}.7^{12}+9.5^{11}.7^{11}}\)
Bài 1: rút gọn các phân số sau:
a) \(\frac{3^{10}.\left(-5\right)^{21}}{\left(-5\right)^{20}.3^{12}}\)
b) \(\frac{-11^5.13^7}{11^5.13^8}\)
c) \(\frac{2^{10}.3^{10}-2^{10}.3^9}{2^9.3^{10}}\)
d) \(\frac{5^{11}.7^{12}+5^{11}.7^{11}}{5^{12}.7^{12}+9.5^{11}.7^{11}}\)
Rút gọn: a) \(\frac{2^{10}.3^{10}-2^{10}.3^9}{2^9.3^{ }^{10}}\) b) \(\frac{5^{11}.7^{12}+5^{11}.7^{11}}{5^{12}.7^{12}+9.5^{11}.7^{11}}\)
\(a,\frac{2^{10}.3^{10}-2^{10}.3^9}{2^9.3^{10}}=\frac{2^{10}.3^9\left(3-1\right)}{2^9.3^{10}}=\frac{2.2}{3}=\frac{4}{3}\)
\(b,\frac{5^{11}.7^{12}+5^{11}.7^{11}}{5^{12}.7^{12}+9.5^{11}.7^{11}}=\frac{5^{11}.7^{11}\left(7+1\right)}{5^{11}.7^{11}\left(5.7+9\right)}=\frac{8}{44}=\frac{2}{11}\)
học tốt
a)
\(\frac{2^{10}.3^{10}-2^{10}.3^9}{2^9.3^{10}}\)
\(=\frac{2^{10}.3^9\left(3-1\right)}{2^9.3^{10}}\)
\(=\frac{2.2}{3}\)
\(=\frac{4}{3}\)
b)
\(\frac{5^{11}.7^{12}+5^{11}.7^{11}}{5^{12}.7^{12}+9.5^{11}.7^{11}}\)
\(=\frac{5^{11}.7^{11}\left(7+1\right)}{5^{11}.7^{11}\left(5.7+9\right)}\)
\(=\frac{8}{35+9}\)
\(=\frac{8}{44}\)
\(=\frac{2}{11}\)
A=1/7.5/9+5/9.1/7+5/9.3/7
giải nhanh giúp mình nhé
A = \(\dfrac{5}{9}\cdot\left(\dfrac{1}{7}+\dfrac{1}{7}+\dfrac{3}{7}\right)\)
=\(\dfrac{5}{9}\cdot\dfrac{5}{7}=\dfrac{25}{63}\)
a,(2^10.3^10-2^10.3^9) : (2^9.3^10)
b,(11.3^22.3^7-9^15) : (2.3^14)^2
c,(5^11.7^12+5^11.7^12) : (5^12.7^11+9.5^11.7^11
. ((((^ là mũ)))))🍭