Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a) \(74\frac{19}{35}.\frac{7}{90}+15\frac{16}{35}.\frac{7}{90}+2\frac{14}{90}\)
= \(\left(74\frac{19}{35}+15\frac{16}{35}\right).\frac{7}{90}+2\frac{14}{90}\)
= 90 . 7/90 + 194/90
= 630/90 + 194/90
= 824/90 = 412/45
b) (-2/5 + 3/7) - (4/9 + 12/20 - 13/35) + 7/35
= -2/5 + 3/7 - 4/9 - 3/5 + 13/35 + 7/35
= (-2/5 - 3/5) + 3/7 - 4/9 + (13/35 + 7/35)
= -1 + 3/7 - 4/9 + 4/7
= -1 + (3/7 + 4/7) - 4/9
= -1 + 1 - 4/9 = -4/9
c.
\(\frac{1}{3}\times\frac{5}{7}-\frac{7}{27}\times\frac{36}{14}\)
\(=\frac{1}{3}\times\frac{5}{7}-\frac{7}{3\times9}\times\frac{4\times9}{7\times2}\)
\(=\frac{1}{3}\times\frac{5}{7}-\frac{1}{3}\times\frac{4}{6}\)
\(=\frac{1}{3}\times\left(\frac{5}{7}-\frac{4}{6}\right)\)
\(=\frac{1}{3}\times\left(\frac{30-38}{42}\right)\)
\(=\frac{1}{3}\times\frac{-8}{42}\)
\(=-\frac{4}{63}\)
Chúc bạn học tốt
Giup tui voi !!!!!!!!!!!!!!!!!!!!!!!!!!! Mai phai nop roi !!!!!!!!!!!!!!!!!!!
\(A=\frac{21.99+21}{35.201-35}=\frac{21\left(99+21\right)}{35\left(201-1\right)}=\frac{21.\left(99+1+20\right)}{35.200}=\frac{21.120}{35.200}=\frac{\left(3.7\right).\left(2.2.3.\right)10}{\left(5.7\right).\left(2.2.5\right).10}=\frac{3.3}{5.5}=\left(\frac{3}{5}\right)^2\)
\(B=\frac{\left(-2\right)^{36}.3^{17}}{3^{18}.2^{35}}=\frac{2^{36}.3^{17}}{2^{35}.3^{18}}=2^{\left(36-35\right)}.3^{17-18}=2.3^{-1}=\frac{2}{3}\)
\(C=\frac{7^{100}-7^{99}}{7^{98}-7^{97}}=\frac{7^{99}\left(7^1-7^0\right)}{7^{97}\left(7^1-7^0\right)}=7^{99-97}.\frac{\left(7-1\right)}{7-1}=7^2.1=49\)
mấy bn giải chi tiết giúp mk nhé !