Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a)\(\frac{15\times3^5}{27^3\times10^2}=\frac{5\times3^6}{3^9\times5\times20}=\frac{1}{3^3\times20}=\frac{1}{540}\)
b) đề thiếu
c) \(\frac{81^{14}\times3^{17}}{27^{10}\times9^{15}}=\frac{\left(9^2\right)^{14}\times3^{17}}{3^{10}\times9^{10}\times9^{15}}=\frac{9^{28}\times3^{17}}{3^{10}\times9^{25}}=\frac{9^3\times3^7}{1}=1594323\)
Không chép lại đầu bài nha!
=\(\frac{5-3}{3.5}+\frac{9-5}{5.9}+\frac{17-9}{9.17}\)
=\(\frac{1}{3}-\frac{1}{5}+\frac{1}{5}-\frac{1}{9}+\frac{1}{9}-\frac{1}{11}\)
=\(\frac{1}{3}-\frac{1}{11}\)
=\(\frac{8}{33}\)
\(F=\frac{15.3^{11}+4.27^4}{9^7}=\frac{5.3.3^{11}+4.\left(3^3\right)^4}{\left(3^2\right)^7}=\frac{5.3^{12}+4.3^{12}}{3^{14}}=\frac{3^{12}.\left(5+4\right)}{3^{14}}=\frac{3^{12}.9}{3^{12}.9}=1\)
\(G=\frac{5.2^{13}.4^{11}-16^9}{\left(3.2^{17}\right)^2}\)
\(G=\frac{5.2^{13}.\left(2^2\right)^{11}-\left(2^4\right)^9}{3^2.2^{34}}\)
\(G=\frac{5.2^{13}.2^{22}-2^{36}}{3^2.2^{34}}\)
\(G=\frac{5.2^{35}-2^{36}}{3^2.2^{34}}\)
\(G=\frac{2^{35}.\left(5-2\right)}{3^2.2^{34}}\)
\(G=\frac{2^{35}.3}{3^2.2^{34}}=\frac{2}{3}\)
\(\left(15.3^{42}-9^{20}\right):27^3\)
\(=\left(5.3.3^{42}-3^{40}\right):3^9\)
\(=\left(5.3^{43}-3^{40}\right):3^9\)
\(=3^{40}\left(5.3^3-1\right):3^9\)
\(=3^{31}\left(5.3^3-1\right)\)
\(=134.3^{31}\)
\(\left(15.3^{42}-9^{20}\right):27^3=15.3^{42}:27^3-9^{20}:27^3\\ \\ =15.3^{42}:\left(3^3\right)^3-9^{20}:9^3:3^3=15.3^{33}-\left(3^2\right)^{20}:\left(3^2\right)^3:3^3\)
\(=15.3^{33}-3^{40}:3^6:3^3=15.3^{33}-3^{31}\\ \\ =15.3^2.3^{31}-3^{31}=135.3^{31}-3^{31}\\ \\ =3^{31}.\left(135-1\right)=3^{31}.134\)
\(c)\) \(C=\frac{\frac{2}{7}+\frac{2}{5}+\frac{2}{17}-\frac{2}{293}}{\frac{3}{7}+\frac{3}{5}+\frac{3}{17}-\frac{3}{293}}\)
\(C=\frac{2\left(\frac{1}{7}+\frac{1}{5}+\frac{1}{17}-\frac{1}{293}\right)}{3\left(\frac{1}{7}+\frac{1}{5}+\frac{1}{17}-\frac{1}{193}\right)}\)
\(C=\frac{2}{3}\)
Bạn Cô nàng Thiên Bình làm đúng hết òi =.=
a=7.[1/8+1/27-1/49]
------------------------
11.[1/8+1/27-1/49]
=7/11
cau b,c tuong tu nha h mk
a) Ta có: \(\dfrac{5}{8}+\dfrac{3}{17}+\dfrac{4}{18}+\dfrac{20}{-17}+\dfrac{-2}{9}+\dfrac{21}{56}\)
\(=\left(\dfrac{3}{17}-\dfrac{20}{17}\right)+\left(\dfrac{2}{9}-\dfrac{2}{9}\right)+\left(\dfrac{5}{8}+\dfrac{3}{8}\right)\)
\(=-1+1=0\)
b) Ta có: \(\left(\dfrac{9}{16}+\dfrac{8}{-27}\right)+\left(1+\dfrac{7}{16}+\dfrac{-19}{27}\right)\)
\(=\left(\dfrac{9}{16}+\dfrac{7}{16}\right)+\left(\dfrac{-8}{27}-\dfrac{19}{27}\right)+1\)
=1-1+1=1
Kết quả số hơi to đấy,ở chỗ mình thì bài này làm như 1 bài rút gọn lại biểu thức nhìn cho đơn giản hơn thôi
\(\dfrac{-8}{15}.\dfrac{3}{7}.\dfrac{15}{-8}.14=\left(\dfrac{-8}{15}.\dfrac{15}{-8}\right).\left(\dfrac{3}{7}.14\right)=1.6=6\)
\(\dfrac{17}{27}.\dfrac{13}{9}-\dfrac{4}{9}.\dfrac{17}{27}=\dfrac{17}{27}.\left(\dfrac{13}{9}-\dfrac{4}{9}\right)=\dfrac{17}{27}.1=\dfrac{17}{27}\)
Ủa bài đâu r