Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
B1:
Ta có: \(\frac{4^6.9^5+6^9.120}{8^4.3^{12}-6^{11}}=\frac{2^{12}.3^{10}-2^9.3^9.2^3.3.5}{2^{12}.3^{12}-2^{11}.3^{11}}\)
\(=\frac{2^{12}.3^{10}-2^{12}.3^{10}.5}{2^{12}.3^{12}-2^{11}.3^{11}}=\frac{2^{12}.3^{10}.\left(1-5\right)}{2^{11}.3^{11}.\left(2.3-1\right)}\)
\(=\frac{2.\left(-4\right)}{3.5}=-\frac{8}{15}\)
B2:
Ta có: \(1+3+5+...+x=1600\)
\(\Leftrightarrow\frac{\left(x+1\right)\cdot\left(\frac{x-1}{2}+1\right)}{2}=1600\)
\(\Leftrightarrow\left(x+1\right)\cdot\frac{x+1}{2}=3200\)
\(\Leftrightarrow\left(x+1\right)^2=6400\)
Xét theo dãy tăng tiến ta thấy được giá trị của x càng tăng
=> x dương => x + 1 dương
\(\Rightarrow x+1=80\)
\(\Rightarrow x=79\)
\(\frac{10.\left(4^6.9^5-6^9.120\right)}{8^4.3^{12}-6^{11}}=\frac{10.4^6.9^5-10.6^9.120}{\left(2^3\right)^4.3^{12}-6^{11}}=\frac{2.5.\left(2^2\right)^6.\left(3^2\right)^5-2.5.6^9.2^3.3.5}{2^{12}.3^{12}-6^{11}}\)
\(=\frac{2.5.2^{12}.3^{10}-2^4.3.5^2.6^9}{6^{12}-6^{11}}=\frac{2^{13}.5.3^{10}-6.2^3.5^2.6^9}{6^{11}.\left(6-1\right)}\)
\(=\frac{6^{10}.2^3.5-6^{10}.2^3.5^2}{6^{11}.5}=\frac{6^{10}.2^3.5.\left(1-5\right)}{6^{11}.5}\)
\(=\frac{2^3.\left(-4\right)}{6}=\frac{8.\left(-4\right)}{6}=\frac{-32}{6}=\frac{-16}{3}\)
46.95+69.120 / 84.312-611
=(22)6.(32)5+(2.3)9.23.3.5 / (23)4.312-(2.3)11
=212.310+29.39.23.3.5 / 212.312-211.311
=212.310+212.310.5 / 211.311.(2.3-1)
=212.310.(1+5) / 211.311.(6-1)
=212.310.6 / 211.311.5
=213.311 / 211.311.5
=22/5
=4/5
A=1+2+22+23+...+263
2A=2+22+23+...+263+264
\(-\)
\(A=1+2+2^2+....+2^{63}\)
\(A=2^{64}-1\)
Vậy A=264-1
\(10.4^6.9^5+6^9.120:8^4.3^{12}-6^{11}\)
\(=2.5.2^{12}.3^{10}+3^9.2^9.2^3.3.5:2^{12}.3^{12}-3^{11}.2^{11}\)
\(=5.2^{13}.3^{10}+2^{12}.5:2^{12}.3^{22}-3^{11}.2^{11}\)
\(=5.2^{13}.3^{10}+5.3^{22}-3^{11}.2^{11}\)
\(=5.3^{10}.\left(2^{13}+3^{12}\right)-3^{11}.2^{11}\)