Cái gì mà tùm lum thế

de gi ma dai, ghi lon xon, chang hieu gi ca??

       \(\frac{5.2^{30}.3^{18}-4.3^{20}.2^{27}}{5.2^9.2^{19}.3^{19}-7.2^{29}.3^{18}}\)

\(=\frac{5.2^{28}.2^2.3^{18}-4.3^{18}.3^2.2^{27}}{5.2^{28}.3^{18}.3-7.2^{27}.2^2.3^{18}}\)

\(=\frac{3^{18}.\left(5.2^{28}.4-4.9.2^{27}\right)}{3^{18}.\left(5.3.2^{28}-7.2^{27}.4\right)}\)

\(=\frac{20.2^{28}-9.2.2.2^{27}}{15.2^{28}-14.2.2^{27}}\)

\(=\frac{2^{28}.20-18.2^{28}}{15.2^{28}-14.2^{28}}\)

\(=\frac{2^{28}.\left(20-18\right)}{2^{28}.\left(15-14\right)}\)

\(=\frac{2^{28}.2}{2^{28}1}\)

\(=2\)

=2/1 = 2

a)\(A=\frac{5.2^{13}.2^{22}-2^{36}}{\left(3.2^{17}\right)^2}\)

\(A=\frac{5.2^{35}-2^{36}}{3^2.2^{34}}\)

\(A=\frac{2^{35}\left(5-2\right)}{3^2.2^{34}}\)

\(A=\frac{2.3}{3^2}=\frac{2}{3}\)

b) \(B=\frac{2^{19}.27^3+15.4^9.9^4}{6^9.2^{10}+12^{10}}\)

\(B=\frac{2^{19}.3^9+3.5.2^{18}.3^8}{2^9.3^9.2^{10}+2^{20}.3^{10}}\)

\(B=\frac{2^{18}.3^9\left(2+5\right)}{2^{19}.3^9\left(2+3\right)}\)

\(B=\frac{7}{2.5}=\frac{7}{10}\)

Ta có: \(\frac35\cdot\frac{11}{13}+\frac25+\frac35\cdot\frac{2}{13}\)

\(=\frac35\left(\frac{11}{13}+\frac{2}{13}\right)+\frac25\)

\(=\frac35+\frac25=\frac55=1\)

\(\frac35\) x \(\frac{11}{13}\) + \(\frac25\) + \(\frac35\) x \(\frac23\)

= \(\frac35\) x ( \(\frac{11}{13}+\frac{2}{13}\) ) + \(\frac25\)

= \(\frac35\) x 1 + \(\frac25\)

= \(\frac35+\frac25\)

= 1

bằng 2. nhấn đúng cho mih nha

tố uyên sai rồi

=2 

 bạn bấm máy tính hoặc tính theo kiểu rút gọn cũng ra

Đây là bài đội tuyển bạn ơi

Đặt A = 1 x 2 + 2 x 3 + ... + 199 x 200

3A = 1 x 2 x 3 + 2 x 3 x (4-1) + .... + 199 x 200 x (201 - 198)

3A = 1 x 2 x 3 + 2 x 3 x 4 - 1 x 2 x 3 +.... + 199 x 200 x 201 - 198 x 199 x 200

3A = ( 1 x 2 x 3 - 1 x 2 x 3) + ( 2 x 3 x 4 - 2 x 3 x 4) + ....... + (198 x 199 x 200 - 198 x 199 x 200) + 199 x 200 x 201

Do đó A = 67 x 200 x 199 = 2666600 

Đặt A=1x2+2x3+3x4+4x5+........+199x200

Ta có:

 3A=1x2x3+2x3x3+3x4x3+.......+199x200x3

3A=1x2x3+2x3x(4-1)+3x4x(5-2)+....+199x200x(201-198)

3A=1x2x3+2x3x4-1x2x3+3x4x5-2x3x4+.............+199x200x201-198x199x200

3A=199x200x201

A=39800x201:3

A=39800x67

A=2666600

Vậy 1x2+2x3+3x4+........+199x200=2666600

a > 5 nhân 2¹⁹

giải rõ ra 

\(=\dfrac{5\cdot2^{30}\cdot3^{18}-2^{29}\cdot3^{20}}{5\cdot2^{28}\cdot3^{19}-7\cdot2^{29}\cdot3^{18}}\)

\(=\dfrac{2^{29}\cdot3^{18}\left(5\cdot2-9\right)}{2^{28}\cdot3^{18}\left(5\cdot3-7\cdot2\right)}=2\)