\(2^2\cdot3^4=4\cdot81=324 \)

\(2^2\cdot3^2\cdot5=4\cdot9\cdot5=20\cdot5=100\)

\(121\cdot75\cdot130\cdot169=9075\cdot130\cdot169=1179750\cdot169=199377750\)

\(39\cdot60\cdot11\cdot198=2340\cdot11\cdot198=25740\cdot198=5096520\)

............Học tốt ^_^..............

Chúc học tốt!!!!

a,\(\frac{2^3.3^4}{2^2.3^2.5}=\frac{2.3^2}{5}=\frac{2.9}{5}=\frac{18}{5}\)

b, \(\frac{2^4.5^2.11^2.7}{2^3.5^3.7^2.11}=\frac{2.11}{5.7}=\frac{22}{35}\)

c,\(\frac{1998.1990+3978}{1992.1991-3984}=\frac{18.111.1990+18.221}{24.83.1991-166.24}\)

                                           \(=\frac{18.\left(111.1990+221\right)}{24.\left(83.1991-166\right)}\)

                                           \(=\frac{3.221111}{4.165087}=\frac{221111}{4.55029}=\frac{221111}{220116}\)

                                           \(\)

a) 2^3 . 3^4/2^2 . 3^2 . 5

= 8 . 81/4 . 9 . 5 

=7290

c) \(\frac{1998.1990+3978}{1992.1991-3984}\)

= \(\frac{1998.1990+1998.2}{1992.1991-1992.2}\)

=\(\frac{1998.\left(1990+2\right)}{1992.\left(1991-2\right)}\)

= \(\frac{1998.1992}{1992.1989}\)

= \(\frac{1998}{1989}\)

a/ \(\frac{2^3.3^4}{2^2.3^2.5}=\frac{2^1.3^2}{1.1.5}=\frac{2.9}{5}=\frac{18}{5}\)

b/ \(\frac{2^4.5^2.11^2.7}{2^3.5^3.7^2.11}=\frac{2.11}{5.7}=\frac{22}{35}\)

c/ Sửa đề: \(\frac{1989.1990+3978}{1992.1991-3984}\)

\(=\frac{1989.1990+1989.2}{1992.1991-1992.2}\)

\(=\frac{1989.\left(1990+2\right)}{1992.\left(1991-2\right)}\)

\(=\frac{1989.1992}{1992.1989}\)

\(=1\)

P/s: Lần sau bạn đăng đề thì nhớ sử dụng Công thức trực quan nhé!

giúp mình với mọi người ơi, mình cần gấp :(

\(\dfrac{121\times75\times130\times169}{39\times60\times11\times198}\)

\(=\dfrac{25\times169}{6\times18}\)

\(=\dfrac{4225}{108}\)

668068830000

= 199377750/5096520

=4225/108

a) \(\frac{5}{12}-\frac{3}{-16}+\frac{3}{4}\)

\(=\frac{5}{12}-\left(-\frac{3}{16}\right)+\frac{3}{4}\)

\(=\frac{5}{12}+\frac{3}{6}+\frac{3}{4}\)

\(=\frac{20+9+36}{48}\)

\(=\frac{65}{48}\)

Mấy câu kia lát làm :))

b) \(\frac{17}{-34}+\frac{25}{75}+\frac{121}{132}\)

\(=-\frac{1}{2}+\frac{1}{3}+\frac{121}{123}\)

\(=-\frac{123}{246}+\frac{82}{246}+\frac{242}{246}\)

\(=\frac{-123+82+242}{246}\)

\(=\frac{201}{246}=\frac{67}{82}\)

c) \(-\frac{7}{21}+\left(1+\frac{1}{3}\right)\)

\(=-\frac{7}{21}+1+\frac{1}{3}\)

\(=-\frac{1}{3}+1+\frac{1}{3}\)

= 0 + 1

= 1

a: \(=3\sqrt{5}+2\sqrt{5}-2\sqrt{5}=3\sqrt{5}\)

b: \(=2\sqrt{2}+2\sqrt{2}+5\sqrt{2}=9\sqrt{2}\)

c: \(=4\sqrt{3}+3\sqrt{3}-3\sqrt{5}+2\sqrt{5}=7\sqrt{3}-\sqrt{5}\)

d: \(=5\sqrt{3}+4\sqrt{3}-10\sqrt{3}=-\sqrt{3}\)

e: \(=\left(\sqrt{7}-2\sqrt{3}\right)\cdot\sqrt{7}+2\sqrt{21}\)

=7-2*căn 21+2*căn 21

=7

f: \(=\left(2\sqrt{11}-3\sqrt{2}\right)\cdot\sqrt{11}+3\sqrt{22}\)

=22-3*căn 22+3*căn 22

=22

a) \(3\sqrt{5}+\sqrt{20}-2\sqrt{5}\)

\(=3\sqrt{5}+2\sqrt{5}-2\sqrt{5}\)

\(=3\sqrt{5}\)

b) \(2\sqrt{2}+\sqrt{8}+\sqrt{50}\)

\(=2\sqrt{2}+2\sqrt{2}+5\sqrt{2}\)

\(=9\sqrt{5}\)

c) \(4\sqrt{3}+\sqrt{27}-\sqrt{45}+2\sqrt{5}\)

\(=4\sqrt{3}+3\sqrt{3}-3\sqrt{5}+2\sqrt{5}\)

\(=7\sqrt{3}-\sqrt{5}\)

d) \(\sqrt{75}+\sqrt{48}-\sqrt{300}\)

\(=5\sqrt{3}+4\sqrt{3}-10\sqrt{3}\)

\(=-\sqrt{3}\)

e) \(\left(\sqrt{28}-\sqrt{12}-\sqrt{7}\right)\sqrt{7}+2\sqrt{21}\)

\(=\left(2\sqrt{7}-2\sqrt{3}-\sqrt{7}\right)\sqrt{7}+2\sqrt{21}\)

\(=\left(\sqrt{7}-2\sqrt{3}\right)\sqrt{7}+2\sqrt{21}\)

\(=7-2\sqrt{21}+2\sqrt{21}\)

\(=7\)

f) \(\left(\sqrt{99}-\sqrt{18}-\sqrt{11}\right)\sqrt{11}+3\sqrt{22}\)

\(=\left(3\sqrt{11}-3\sqrt{2}-\sqrt{11}\right)\sqrt{11}+3\sqrt{22}\)

\(=\left(2\sqrt{11}-3\sqrt{2}\right)\sqrt{11}+3\sqrt{22}\)

\(=22-3\sqrt{22}+3\sqrt{22}\)

\(=22\)

g) \(3\sqrt{45}-5\sqrt{125x}+7\sqrt{20x}+28\)

\(=9\sqrt{5}-25\sqrt{5x}+14\sqrt{5x}+28\)

\(=9\sqrt{5}-11\sqrt{5x}+28\)