Tính bằng cách hợp lý:
-22.83 + (-83).(-72)
Tính hợp lý (nếu có thể) : -72 . (83+99) - 72 . (-83)
Giúp tui nha
=-72.83 +99-72.(-83) + 1
=-72.[83+(-83)] . (99+1)
=-72. 0 .100
=0
hihi
bạn lấy -72 là số chung rồi nhân với [(83+99) - 72. (-83)] kết quả của [(83+99) - 72. (-83)] bạn tự tính nha rồi bạn sẽ ra kết quả
2023 x 14 + 2023 x 83 +97
78 x 31 + 78 x 24 + 78 x 17 + 78 x 22 x 72
371 x 69 + 371 x 14 + 629 x 83
91 x 51 + 49 x 163 - 49 x 72
3 x 12 x 17 + 4 x 9 x 81 + 2 x 6 x 6
42 x 17 + 58 x 83 x 42 x 83 + 42 x 83 + 58 x 17
tính bằng cách hợp lý nhất
`@` `\text {Ans}`
`\downarrow`
`2023 \times 14 + 2023 \times 83+97`
`= 2023 \times (14+83) + 97`
`= 2023 \times 97 + 97`
`= 196231 +97`
`= 196328`
`78 \times 31+78 \times 24+78 \times 17+78 \times 22 \times 72`
`= 78 \times (31+24+17+22 \times 72)`
`= 78 \times (31+24+17+1584)`
`= 78 \times 1656`
`= 129168`
`371 \times 69+371 \times 14+629 \times 83`
`= 371 \times (69+14) + 629 \times 83`
`= 371 \times 83 + 629 \times 83`
`= 83 \times (371+629)`
`= 83 \times 1000`
`= 83000`
`91 \times 51+49 \times 163-49 \times 72`
`= 91 \times 51 + 49 \times (163-72)`
`= 91 \times 51+49 \times 91`
`= 91 \times (51+49)`
`= 91 \times 100`
`= 9100`
`3 \times 12 \times 17 + 4 \times 9 \times 81 + 2 \times 6 \times 6`
`= 9 \times 4 \times 17 + 4 \times 9 \times 81 + 4 \times 9 \times 2`
`= 9 \times 4 \times (17+81+2)`
`= 36 \times 100`
`= 3600`
`42 \times 17 + 58 \times 83 \times 42 \times 83 + 42 \times 83 + 17`
`= 17 \times (42+58) + 42 \times 83 \times (58 \times 83 +1)`
`= 17 \times 100 + 3486 \times 4815`
`= 1700 + 16785090`
`= 16786790`
Tính bằng cách hợp lý nhất : 649 x 94 - 83 x 649 - 649
= 649 x (94 - 83 - 1)
= 649 x 10
= 649
học tốt nha bạn
649 x 94 -83 x 649 - 649
=649 x 94 - 83 x 649 - 649 x 1
=649 x (94 - 83 - 1)
=649 x 10
=6490
bằng 6490 nha bạn
Chúc bạn hok tốt
T.I.C.K cho mình nah
Tính bằng cách hợp lý: (-48).72 + 36.(-304)
( − 48 ) .72 + 36. ( − 304 ) = ( − 48 ) .2.36 + 36. ( − 304 ) = ( − 96 ) .3 + 36. ( − 304 )
tính bằng cách hợp lý
-49+(-317-51)
-143-(57-48)
-237-(-83+63)
-573+(-38-27)
-2021+(37-79)
-1983-(17+183)
tính bằng cách hợp lý
(217+172).(915-315).(24-42)
(71997-71995):(71994.7)
(12+23+34+45).(13+23+3343).(38-812)
(28+83):(25.23)
\(\left(2^{17}+7^2\right).\left(9^{15}-3^{15}\right).\left(2^4-4^2\right)\)
\(=\left(2^{17}+7^2\right).\left(9^{15}-3^{15}\right).\left(16-16\right)\)
\(=\left(2^{17}+7^2\right).\left(9^{15}-3^{15}\right).0\)
\(=0\)
-------------------------------------------------
\(\left(7^{1997}-7^{1995}\right):\left(7^{1994}.7\right)\)
\(=\left[7^{1995}\left(7^2-1\right)\right]:7^{1995}\)
\(=7^{1995}.48:7^{1995}\)
\(=48\)
-------------------------------------------------
\(\left(1^2+2^3+3^4+4^5\right).\left(1^3+2^3+3^3+4^3\right).\left(3^8-81^2\right)\)
\(=\left(1^2+2^3+3^4+4^5\right).\left(1^3+2^3+3^3+4^3\right).\left(6561-6561\right)\)
\(=\left(1^2+2^3+3^4+4^5\right).\left(1^3+2^3+3^3+4^3\right).0\)
\(=0\)
-------------------------------------------------
\(\left(2^8+8^3\right):\left(2^5.2^3\right)\)
\(=\left[2^8+\left(2^3\right)^3\right]:2^8\)
\(=\left(2^8+2^9\right):2^8\)
\(=2^8.\left(1+2\right):2^8\)
\(=2^8.3:2^8\)
\(=3\)
\((2^{17}+17^{2}).(9^{15}-3^{15}).(2^{4}-4^{2})\)
\(=(2^{17}+17^{2}).(9^{15}-3^{15}).(16-16)\)
\(=(2^{17}+17^{2}).(9^{15}-3^{15}).0\)
\(=0\)
\((7^{1997}-7^{1995}):(7^{1994}.7)\)
\(=(7^{1997}-7^{1995}):7^{1995}\)
\(=7^{1997}:7^{1995}-7^{1995}:7^{1995}\)
\(=7^{2}-1=49-1=48\)
\(1^{2}+2^{3}+3^{4}+4^{5}).(1^{3}+2^{3}+3^{3}+4^{3}).(3^{8}-81^{2})\)
\(=(1^{2}+2^{3}+3^{4}+4^{5}).(1^{3}+2^{3}+3^{3}+4^{3}).(6561-6561)\)
\(=(1^{2}+2^{3}+3^{4}+4^{5}).(1^{3}+2^{3}+3^{3}+4^{3}).0\)
\(=0\)
\((2^{8}+8^{3}):(2^{5}.2^{3})\)
\(=[2^{8}+(2^{3})^{3}]:2^{8}\)
\(=(2^{8}+2^{9}):2^{8}\)
\(=2^{8}:2^{8}+2^{9}:2^{8}\)
\(=1+2=3\)
Tính bằng cách hợp lý nhất
29*72-55*36+997*36
dấu mũ hay dấu nhân z
= 29.2.36 - 55 . 36 + 997. 36
= 36. (58 - 55 + 997)
= 36. 1000=36000
Tính bằng cách hợp lý:
a) ( − 4 ) .13. ( − 250 )
b) ( − 37 ) .84 + 37. ( − 16 )
c) 25. ( − 5 ) .4. ( − 20 )
d) ( − 48 ) .72 + 36. ( − 304 )
a) ( − 4 ) .13. ( − 250 ) = ( − 4 ) . ( − 250 ) .13 = 1000.13 = 13000
b) ( − 37 ) .84 + 37. ( − 16 ) = ( − 37 ) .84 + ( − 37 ) .16 = ( − 37 ) . ( 84 + 16 ) = ( − 37 ) .100 = − 3700
c) 25. ( − 5 ) .4. ( − 20 ) = 25.4. ( − 5 ) . ( − 20 ) = 100.100 = 10000
d) ( − 48 ) .72 + 36. ( − 304 ) = ( − 48 ) .2.36 + 36. ( − 304 ) = ( − 96 ) .3 + 36. ( − 304 )
tính bằng cách thuận tiện nhất (18 x 83 + 9 x 17x2- 3x60x6):72
( 18 x 83 + 9 x 17 x 2 - 3 x 60 x 6 ) : 72 = ( 18 x 83 + 18 x 17 - 18 x 60 ) : 72
= [ 18 x ( 83 + 17 - 60 ) ] : 72
= ( 18 x 40 ) : 72
= 720 : 72
= 10
(18.83+9.2.17-3.6.60):72
=(18.83+18.17-18.60):72
=18.(83+17-60):72
=18.40:72
=720:72
=10