Tính BCNN\(\left(\frac{16}{21},\frac{56}{27}\right)\)(Trình bày rõ => tick )
Bài 1 : Tính BCNN của \(\frac{16}{21}\) và \(\frac{56}{27}\)( Giải rõ => tick )
Tính:
A = $5\frac{3}{7}+\left(-5,35\right)+\frac{1}{3}+\left(-2,41\right)+\frac{3}{21}+\left(-1,24\right)$537 +(−5,35)+13 +(−2,41)+321 +(−1,24)
B = $4\frac{25}{16}+25.\left(\frac{9}{16}-\frac{117}{64}\right):\frac{27}{8}$42516 +25.(916 −11764 ):278
Trình bày cách giải và đáp án giúp mình nha! ^^
Tính:
A = \(5\frac{3}{7}+\left(-5,35\right)+\frac{1}{3}+\left(-2,41\right)+\frac{3}{21}+\left(-1,24\right)\)
B = \(4\frac{25}{16}+25.\left(\frac{9}{16}-\frac{117}{64}\right):\frac{27}{8}\)
Mấy dấu gạch không phải là trị tuyệt đối đâu mà khi mình ghi thì nó có sẵn
Trình bày cách giải và đáp án giúp mình nha! ^^
Tính:
\(\frac{1}{2}+\left(\frac{16}{21}+\frac{27}{13}\right)-\left(\frac{14}{13}-\frac{5}{21}\right)\)
\(\frac{1}{2}+\left(\frac{16}{21}+\frac{27}{13}\right)-\left(\frac{14}{13}-\frac{5}{21}\right)\)
\(=\frac{1}{2}+\frac{16}{21}+\frac{27}{13}-\frac{14}{13}+\frac{5}{21}\)
\(=\left(\frac{16}{21}+\frac{5}{21}\right)+\left(\frac{27}{13}-\frac{14}{13}\right)+\frac{1}{2}\)
\(=1+1+\frac{1}{2}\)
\(=\frac{5}{2}\)
#)Giải :
\(\frac{1}{2}+\left(\frac{16}{21}+\frac{27}{13}\right)-\left(\frac{14}{13}-\frac{5}{21}\right)\)
\(=\frac{1}{2}+\frac{16}{21}+\frac{27}{13}-\frac{14}{13}+\frac{5}{21}\)
\(=\frac{1}{2}+\left(\frac{16}{21}+\frac{5}{21}\right)+\left(\frac{27}{13}-\frac{14}{13}\right)\)
\(=\frac{1}{2}+1+1\)
\(=2\frac{1}{2}=\frac{5}{2}\)
\(\frac{1}{2}+\left(\frac{16}{21}+\frac{27}{13}\right)-\left(\frac{14}{13}-\frac{5}{21}\right)\)
\(=\frac{1}{2}+\frac{16}{21}+\frac{27}{13}-\frac{14}{13}+\frac{5}{21}\)
\(=\frac{1}{2}+\left(\frac{16}{21}+\frac{5}{21}\right)+\left(\frac{27}{13}-\frac{14}{13}\right)\)
\(=\frac{1}{2}+1+1\)
\(=1+2+2\)
\(=5\)
Tính nhanh: \(\left(\frac{1}{11\times16}\right)+\left(\frac{1}{16\times21}\right)+\left(\frac{1}{21\times26}\right)+...+\left(\frac{1}{56\times61}\right)+\left(\frac{1}{61\times66}\right)\)
\(\frac{1}{11\times16}+\frac{1}{16\times21}+\frac{1}{21\times26}+...+\frac{1}{56\times61}+\frac{1}{61\times66}\)
\(=\frac{1}{5}\times\left(\frac{1}{11}-\frac{1}{16}+\frac{1}{16}-\frac{1}{21}+\frac{1}{21}-\frac{1}{26}+...+\frac{1}{56}-\frac{1}{61}+\frac{1}{61}-\frac{1}{66}\right)\)
\(=\frac{1}{5}\times\left(\frac{1}{11}-\frac{1}{66}\right)\)
\(=\frac{1}{5}\times\frac{5}{66}\)
\(=\frac{1}{66}\)
\(\frac{1}{11\times16}+\frac{1}{16\times21}+\frac{1}{21\times26}+...+\frac{1}{56\times61}+\frac{1}{61\times66}\)
\(=\frac{1}{5}\times\left(\frac{5}{11\times16}+\frac{5}{16\times21}+\frac{5}{21\times26}+...+\frac{5}{56\times61}+\frac{5}{61\times66}\right)\)
\(=\frac{1}{5}\times\left(\frac{1}{11}-\frac{1}{16}+\frac{1}{16}-\frac{1}{21}+\frac{1}{21}-\frac{1}{26}+...+\frac{1}{56}-\frac{1}{61}+\frac{1}{61}-\frac{1}{66}\right)\)
\(=\frac{1}{5}\times\left(\frac{1}{11}-\frac{1}{66}\right)\)
\(=\frac{1}{5}\times\frac{5}{66}=\frac{1}{66}\)
\(\frac{1}{11.16}+\frac{1}{16.21}+\frac{1}{21.26}+...+\frac{1}{61.66}\)
\(=\frac{1}{5}.\left(\frac{5}{11.16}+\frac{5}{16.21}+\frac{5}{21.26}+...+\frac{5}{61.66}\right)\)
\(=\frac{1}{5}.\left(\frac{1}{11}-\frac{1}{16}+\frac{1}{16}-\frac{1}{21}+...+\frac{1}{61}-\frac{1}{66}\right)\)
\(=\frac{1}{5}.\left(\frac{1}{11}-\frac{1}{66}\right)\)
\(=\frac{1}{5}.\frac{5}{66}\)
\(=\frac{1}{66}\)
ĐỀ: THỰC HIỆN PHÉP TÍNH ( Trình bày hộ mình <3 )
a) \(\frac{\left|\left(-5\right)^3\right|^2}{27}.\frac{3}{2^3}.\frac{6^2}{\left(-5\right)^5}\)
b) \(\left(-3\right)^2+\sqrt{\frac{16}{25}-\sqrt{9}+\frac{\sqrt{81}}{\left|-3\right|}}\)
Tính nhanh cái này nha(Trình bày ra đầy đủ ko thì hết 3 tick đó nha)
\(\left(5\frac{3}{7}-2\frac{1}{4}\right):4\frac{43}{56}\)
2/3 nha neu dung k cho mk nhe
Rút gọn biểu thức A = \(\left(2-1\frac{1}{4}\right)\left(2-1\frac{1}{9}\right)\left(2-1\frac{1}{16}\right)...\left(2-1\frac{1}{400}\right)\)
ta dc kết quả là ?
trình bày rõ cách làm ra với nha.
Bài 1 : Tính : A = \(\left(1-\frac{1}{8}\right).\left(1-\frac{1}{9}\right).\left(1-\frac{1}{10}\right)...\left(1-\frac{1}{100}\right)\)( Trình bày rõ => like )
\(A=\left(1-\frac{1}{8}\right)\times\left(1-\frac{1}{9}\right)\times\left(1-\frac{1}{10}\right)\times...\times\left(1-\frac{1}{100}\right)\)
\(A=\frac{7}{8}\times\frac{8}{9}\times\frac{9}{10}\times...\times\frac{98}{99}\times\frac{99}{100}\)
\(A=\frac{7\times8\times9\times...\times98\times99}{8\times9\times10\times...\times99\times100}=\frac{7}{100}\)
=>A=7/8*8/9*9/10*...*99/100
=>A=(7*8*9*...*99)/(8*9*10*...*100)=7/100
Vậy A=.............
\(A=\frac{7}{8}.\frac{8}{9}.\frac{9}{10}.....\frac{99}{100}\)
\(A=\frac{7.8.9.....99}{8.9.10.....100}\)
\(A=\frac{7}{100}\)