64 * 43-16*72
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![](https://rs.olm.vn/images/avt/0.png?1311)
a)BCNN(72,540)=1080
b)BCNN(28,49,64)=3136
c)BCNN(43,53)=2279
![](https://rs.olm.vn/images/avt/0.png?1311)
a: =-64(32+68)=64x100=-6400
b: =76(-54-12+36)=76x(-30)=-2380
c: =19x50+38x5=950+190=1140
![](https://rs.olm.vn/images/avt/0.png?1311)
\(\begin{array}{*{20}{c}}{ - \begin{array}{*{20}{c}}{63}\\{36}\end{array}}\\\hline{\,\,\,\,27}\end{array}\) \(\begin{array}{*{20}{c}}{ - \begin{array}{*{20}{c}}{72}\\{27}\end{array}}\\\hline{\,\,\,45}\end{array}\)
\(\begin{array}{*{20}{c}}{ - \begin{array}{*{20}{c}}{54}\\{16}\end{array}}\\\hline{\,\,\,\,38}\end{array}\) \(\begin{array}{*{20}{c}}{ - \begin{array}{*{20}{c}}{80}\\{43}\end{array}}\\\hline{\,\,\,37}\end{array}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(\dfrac{73}{72}=1+\dfrac{1}{72}\)
\(\dfrac{43}{42}=1+\dfrac{1}{42}\)
\(\dfrac{53}{52}=1+\dfrac{1}{52}\)
\(\dfrac{65}{64}=1+\dfrac{1}{64}\)
\(\dfrac{87}{86}=1+\dfrac{1}{86}\)
mà \(\dfrac{1}{42}>\dfrac{1}{52}>\dfrac{1}{64}>\dfrac{1}{72}>\dfrac{1}{86}\left(42< 52< 64< 72< 86\right)\)
nên \(\dfrac{43}{42}>\dfrac{53}{52}>\dfrac{65}{64}>\dfrac{73}{72}>\dfrac{87}{86}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
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a) Ta có:
16^19=(24)19=276 ; 825=(23)25=275
Vì 76>75 nên 276>275. Vậy 1619>825
b) Ta có:
7245-7244=72(7244-7243)
Vậy 7245-7244 > 7244-7243
c) chịu
a, Ta có:16^19=(2^4)^19=2^76
8^25=(2^3)^25=2^75
Vì 2^75<2^76 nên 8^75<16^19
b,Ta có:72^45-72^74=72(72^44-72^73)
=>72^45-72^44>72^44-72^43
c,MÌNH GIẢI PHẦN NÀY SAU NHÉ!
![](https://rs.olm.vn/images/avt/0.png?1311)
a>\(16^{19}=2^{4^{19}}=2^{76}\\ 8^{25}=2^{3^{25}}=2^{75}\)
16^19>8^25
`64 xx 43 - 16 xx 72`
` = 16 xx 4 xx 43 - 16 xx 72`
` = 16 xx ( 4 xx 43) - 16 xx 72`
` = 16 xx 172 - 16 xx 72`
` = 16 xx ( 172 - 72)`
` = 16 xx 100`
` = 1600`
\(64\times43-16\times72=\left(64\times43\right)-\left(16\times72\right)=2752-1152=1600.\)