tính:
a)\(\frac{4^6.9^5+6^9.120}{8^4.3^{12}-6^{11}}\)
b)\(\frac{2^{15}.9^4}{6^3.8^3}\)
c)\(\frac{8^{10}+4^{10}}{8^4+4^{11}}\)
\(\frac{4^6.9^5+6^9.120}{8^4.3^{12}-6^{11}}.10\)
\(\frac{4^6.9^5+6^9.120}{8^4.3^{12}-6^{11}}.10=\frac{2^{12}.3^{10}+2^9.3^9.120}{2^{12}.3^{12}-2^{11}.3^{11}}.10=\frac{2^{10}.3^{10}\left(2^2+20\right)}{2^{10}.3^{10}\left(6^2-6\right)}.10=\frac{24.10}{30}=8\)
\(10.\frac{4^6.9^5+6^9.120}{8^4.3^{12}-6^{11}}\)
10.46.95+69.120 :; 84.312-611
Tính:
a) (-5)^60.30^5/15^5.5^61 b) (-3)^10.15^5/25^3.(-9)^7
c)4^6.9^5+6^9.120/8^4.3^12-6^11 d) 4^2.25^2+32.125/2^3.5^2
$\frac{4^6.9^5+6^9.120}{8^4.3^{12}-6^{11}}$
Rút gọn biểu thức: \(10.\frac{4^6.9^5+6^9.120}{8^4.3^{12}-6^{11}}\)
tính biểu thức \(10.\frac{4^6.9^5+6^9.120}{8^4.3^{12}-6^{11}}\)
=5^1+3+5+7+.....+49
Số các số hạng từ 1 đến 49 là (49-1):1+1=50
Tổng các số từ 1 đên 49 là (49+1).50:2=1250
=5^1250
\(\frac{20^5.5^{10}}{100^5}.\frac{4^6.9^5+6^9.120}{8^4.3^{12}-6^{11}}\)
\(\left(\frac{4}{9}+\frac{1}{3}\right)^2+\left(\frac{3}{4}\right)^3:\left(\frac{3}{4}\right)^2:\left(\frac{-2}{3}\right)^3\)
tính = cách hợp lí nếu có thể :
\(\frac{10^3+2.5^3+5^3}{55}-\frac{4^6.9^5+6^9.120}{8^4.3^{12}-6^{11}}\)
\(\frac{10^3+2.5^3+5^3}{55}-\frac{4^6.9^5+6^9.120}{8^4.3^{12}-6^{11}}\)\(=\frac{2^3.5^3+2.5^3+5^3}{5.11}-\frac{2^{12}.3^{10}+2^9.3^9.2^3.3.5}{2^{12}.3^{12}-2^{11}.3^{11}}\)
\(=\frac{5^3\left(2^3+2+1\right)}{5.11}-\frac{2^{12}.3^{10}.\left(1+5\right)}{2^{11}.3^{11}.\left(2.3-1\right)}=\frac{5^2.11}{11}-\frac{2.6}{3.5}=25-\frac{4}{5}=\frac{121}{5}\)
Tính hợp lí :
a ) 10 . \(\frac{4^6.9^5+6^9.120}{8^4.3^{12}.6^{11}}\)
Sửa đề : \(10.\frac{4^6.9^5+6^9.120}{8^4.3^{12}-6^{11}}\)
\(10\cdot\frac{4^6\cdot9^5+6^9\cdot120}{8^4\cdot3^{12}-6^{11}}\)
\(=10\cdot\frac{2^{12}\cdot3^{10}+2\cdot9\cdot3^9\cdot2^3\cdot3\cdot5}{2^{12}.3^{12}-2^{11}.3^{11}}\)
\(=10\cdot\frac{2^{12}\cdot3^{10}\cdot\left(1+5\right)}{2^{11}\cdot3^{11}\cdot\left(2\cdot3-1\right)}\)
\(=10\cdot\frac{2\cdot6}{3\cdot5}=8\)
Bài làm:
\(10.\frac{4^6.9^5+6^9.120}{8^4.3^{12}.6^{11}}\)
\(=\frac{2.5.2^{12}.3^{10}+2^9.3^9.2.5.2^2.3}{2^{12}.3^{12}.2^{11}.3^{11}}\)
\(=\frac{2^{13}.3^{10}.5+2^{12}.3^{10}.5}{2^{23}.3^{23}}\)
\(=\frac{2^{12}.3^{10}.5\left(2+1\right)}{2^{23}.3^{23}}\)
\(=\frac{2^{12}.3^{11}.5}{2^{23}.3^{23}}=\frac{5}{2^{11}.3^{12}}\)
sợ sai