Tính nhanh : \(A=490-3100\times7^2+90\times7^2+49\times125\times16\)16
\(\frac{49^{24}\times125^{10}\times2^8-5^{30}\times7^{49}\times4^5}{5^{29}\times16^2\times7^{48}}\) tính giùm mình nha
= (72)24 x (53)10 x 28- 530 x 749 x (22)5 / 529 x (24)2 x 748
= 748 x 530 x 28 - 530 x 749 x 210 / 529x 28 x 748
= 748 x 530 x 28 x (1 - 7 x 22) /529 x 28 x 748
=748 x 530 x 28 x (-27) / 529 x 28 x 748
=5 x (-27) = -135
=
Tính (theo mẫu).
Mẫu: \(\dfrac{2\times3\times7}{5\times7\times3}=\dfrac{2}{5}\)
a) \(\dfrac{12\times11\times13}{13\times17\times11}\) b) \(\dfrac{49\times16\times31}{16\times49\times37}\)
a) = \(\dfrac{12}{17}\)
b) = \(\dfrac{31}{37}\)
\(\frac{l-5l\times7^4+7^3\times25}{7^5\times125-7^3\times50}\)TÍNH NHANH
\(\frac{4\times6\times7}{28\times16\times6}=.................................=\frac{ }{ }\)
\(\frac{4\times6\times7}{28\times16\times6}\)
\(=\frac{4\times6\times7}{4\times7\times16\times6}\)
\(=\frac{1}{16}\)
4 x 6 x 7 / 28 x 16 x 6
= 4 x 6 x 7 / 7 x 4 x 4 x 4 x 6
= 1 / 4 x 4
= 1 / 16
Tk mk nha
\(\frac{4\times6\times7}{28\times16\times6}=\frac{4\times7}{28\times16}\)
\(=\frac{28}{28\times16}\)
\(=\frac{1}{16}\)
Tính.
a) \(\dfrac{5\times6\times12}{6\times12\times7}\) b) \(\dfrac{9\times8\times15}{15\times9\times16}\)
a) \(\dfrac{5\times6\times12}{6\times12\times7}=\dfrac{5}{7}\)
b) \(\dfrac{9\times8\times15}{15\times9\times16}=\dfrac{1}{2}\)
các cậu tính nhanh hộ tớ con này \(\frac{\left(2^3\times5\times7\right)\times\left(5^2\times7^3\right)}{\left(2\times5\times7\right)^2}\)
Làm ơn tớ đang cần gấp
\(\frac{\left(2^3\cdot5\cdot7\right)\cdot\left(5^2\cdot7^3\right)}{\left(2\cdot5\cdot7\right)^2}\)
\(=\frac{2^3\cdot5^3\cdot7^4}{2^2\cdot5^2\cdot7^2}\)
\(=2\cdot5\cdot7^2\)
\(=10\cdot49=490\)
\(\frac{\left(2^3.5.7\right).\left(5^2.7^3\right)}{\left(2.5.7\right)^2}\)
\(=\frac{2^3.5^3.7^4}{2^2.5^2.7^2}\)
\(=2.5.7^2\)
\(=\left(2.5\right).7^2\)
\(=10.49\)
\(=490\)
\(\frac{\left(2^3\times5\times7\right)\times\left(5^2\times7^3\right)}{\left(2\times5\times7\right)^2}=\frac{2^3\times5^3\times7^4}{2^2\times5^2\times7^2}=2\times5\times7^2=10\times49=490\)
Bài 1: Tính
a) \(\dfrac{2\times3\times6\times7}{12\times7\times9\times2}\)
b) \(\dfrac{3\times4\times30\times56}{9\times8\times7\times8\times20}\)
(Các bạn tách ra rồi tính)
tính nhanh
\(5\times7\times77-7\times60+49\times25-15\times42\)
các bn giúp mk nhanh nha
5 x 7 x 77 - 7 x 60 + 49 x 25 - 15 x 42
= (5 x 77) x 7 - 7 x 60 + 7 x 7 x 25 - 15 x 6 x 7
= 385 x 7 - 7 x 60 + 7 x (7 x 25) - 90 x 7
= 385 x 7 - 7 x 60 + 7 x 175 - 90 x 7
= 7 x (385 - 60 + 175 - 90)
= 7 x 410
= 2870
= 7 x 5 x 77 - 7 x 60 + 7 x 7 x 25 - 7 x 6 x 15
= 7 x 5 x 77 - 7 x 5 x 12 + 7 x 5 x 5 x 7 - 7 x 5 x 3 x 6
= 7 x 5 x ( 77 - 12 + 5 x 7 - 3 x 6 )
= 7 x 5 x ( 77 - 12 + 35 - 36 )
= 7 x 5 x ( 65 + 35 - 36 )
= 7 x 5 x ( 100 - 36 )
= 7 x 5 x 64
= 2240
Tính:
\(\frac{exp\left(24\right)}{\frac{25}{2}\%}\times12\frac{5}{4}+\left|-54^2\right|\times\pi+6\)\(\times7\sqrt{65}+\frac{7\times7^2\times7^3\times7^4}{3\times3^2\times3^3\times3^4}\)