Thực hiện các phép tính:
a) \(A=4\frac{25}{16}+25\left(\frac{9}{16}:\frac{125}{64}\right):\frac{-27}{8}\)
b) \(C=\frac{2^3}{3.5}+\frac{2^3}{5.7}+\frac{2^3}{7.9}+...+\frac{2^3}{101.103}\)
Những câu hỏi liên quan
Thực hiện phép tính:
a) \(\frac{-5}{9}.\left(\frac{3}{10}-\frac{2}{5}\right)\)
b) \(2^8:2^5+3^3.2-12\)
c) \(\frac{1}{2}\sqrt{64}-\sqrt{\frac{4}{25}}+1^{2012}\)
d) \(\left(-3\right)^2+\sqrt{\frac{16}{25}}-\sqrt{9}+\frac{\sqrt{81}}{3}\)
\(a,\frac{-5}{9}.\left(\frac{3}{10}-\frac{2}{5}\right)\)
\(=\frac{-5}{9}.\frac{-1}{10}\)
\(=\frac{1}{18}\)
\(b,2^8:2^5+3^3.2-12\)
\(=2^3+9.2-12\)
\(=8+18-12\)
\(=26-12\)
\(=14\)
Câu c,d em chưa học nên không biết làm ạ, mong mọi người thông cảm!!!
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Sửa lại câu b
\(=2^3+27.2-12\)
\(=8+54-12\)
\(=62-12\)
\(=50\)
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15 tháng 4 2019 lúc 18:48
Tính
A= \(\frac{2}{3.5}+\frac{2}{5.7}+\frac{2}{7.9}+...+\frac{2}{19.21}\)
B= \(\frac{3}{11.14}+\frac{3}{14.17}+\frac{3}{17.20}+...+\frac{3}{68.71}\)
C= \(\frac{8}{9}.\frac{15}{16}.\frac{24}{25}.\frac{35}{36}.............................\frac{2499}{2500}\)
\(A=\frac{2}{3.5}+\frac{2}{5.7}+\frac{2}{7.9}+...+\frac{2}{19.21}\)
\(=\frac{1}{3}-\frac{1}{5}+\frac{1}{5}-\frac{1}{7}+\frac{1}{7}-\frac{1}{9}+...+\frac{1}{19}-\frac{1}{21}\)
\(=\frac{1}{3}-\frac{1}{21}\)
\(=\frac{7}{21}-\frac{1}{21}=\frac{6}{21}\)
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\(A=\frac{2}{3.5}+\frac{2}{5.7}+\frac{2}{7.9}+...+\frac{2}{19.21}\)
\(A=\frac{1}{3}-\frac{1}{5}+\frac{1}{5}-\frac{1}{7}+\frac{1}{7}-\frac{1}{9}+...+\frac{1}{19}-\frac{1}{21}\)
\(A=\frac{1}{3}+\left(\frac{1}{5}-\frac{1}{5}\right)+\left(\frac{1}{7}-\frac{1}{7}\right)+\left(\frac{1}{9}-\frac{1}{9}\right)+...+\left(\frac{1}{19}-\frac{1}{19}\right)-\frac{1}{21}\)
\(A=\frac{1}{3}-\frac{1}{21}\)
\(A=\frac{2}{7}\)
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\(B=\frac{3}{11.14}+\frac{3}{14.17}+\frac{3}{17.20}+...+\frac{3}{68.71}\)
\(=\frac{1}{11}-\frac{1}{14}+\frac{1}{14}-\frac{1}{17}+\frac{1}{17}-\frac{1}{21}+...+\frac{1}{68}-\frac{1}{71}\)
\(=\frac{1}{11}-\frac{1}{71}\)
\(=\frac{71}{781}-\frac{11}{781}\)
\(=\frac{60}{781}\)
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Xem thêm câu trả lời
- Thực hiện phép tính :
a)\(5\frac{27}{5}+\frac{27}{23}+0,5-\frac{5}{27}+\frac{16}{23}
\)
b) \(\frac{3}{8}.27\frac{1}{5}-51\frac{1}{5}.\frac{3}{8}+19\)
c) 25.\(\left(\frac{-1}{5}\right)^3+\frac{1}{5}-2.\left(\frac{-1}{2}\right)^2-\frac{1}{2}\)
d) \(35\frac{1}{6}:\left(\frac{-4}{5}\right)-46\frac{1}{6}:\left(\frac{-4}{5}\right)\)
- Giúp mình nha ^^
Xem thêm câu trả lời
Tính
a) \(2\sqrt{\frac{25}{16}}-3\sqrt{\frac{49}{36}}+4\sqrt{\frac{81}{64}}\)
b) \(\left(3\sqrt{2}\right)^2-\left(4\sqrt{\frac{1}{2}}\right)^2+\frac{1}{16}.\left(\sqrt{\frac{3}{4}}\right)^2\)
c) \(\frac{2}{3}\sqrt{\frac{81}{16}}-\frac{3}{4}\sqrt{\frac{64}{9}}+\frac{7}{5}.\sqrt{\frac{25}{196}}\)
a) = \(\frac{7}{2}\)
b) = \(\frac{643}{64}\)
c) = 0
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Thực hiện phép tính:
a,\(16\frac{2}{7}:\left(\frac{-3}{5}\right)+28\frac{2}{7}:\frac{3}{5}\)
b,\(\left(2^2:\frac{4}{3}-\frac{1}{2}\right)\cdot\frac{6}{5}-17\)
c,\(\left(\frac{1}{3}\right)^{50}.\left(-9\right)^{25}-\frac{2}{3}:4\)
Ta có : \(\left(2^2:\frac{4}{3}-\frac{1}{2}\right).\frac{6}{5}-17\)
=\(=\left(4.\frac{3}{4}-\frac{1}{2}\right).\frac{6}{5}-17\)
\(=\frac{5}{2}.\frac{6}{5}-17\)
\(=3-17=-14\)
Tụi quá mới lớp 5 thui
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) \(\left(-3\right)^2+\sqrt{\frac{16}{25}-\sqrt{9}+\frac{\sqrt{81}}{\left|-3\right|}}\)
Thực hiện phép tính (Tính hợp lý nếu có thể)g) frac{3}{5}:left(frac{-1}{15}-frac{1}{6}right)+frac{3}{5}:left(frac{-1}{3}-1frac{1}{15}right)h) 10.sqrt{0,01}.sqrt{frac{16}{9}+3sqrt{49}-frac{1}{6}sqrt{4}}i) frac{2^4.2^6}{left(2^5right)^2}-frac{2^5.15^3}{6^3.10^2}k) (2frac{1}{3}+3frac{1}{2}):left(-4frac{1}{6}+3frac{1}{7}right)+7frac{1}{2}n) 4frac{25}{16}+25left(frac{9}{16}:frac{125}{64}right):frac{-27}{8}m) [1,5+2frac{1}{2}-left(2sqrt{2}right)^2]:[4frac{1}{2}-sqrt{1,96}+0,9]o) frac{5}{21}.left(4frac...
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Thực hiện phép tính (Tính hợp lý nếu có thể)
g) \(\frac{3}{5}:\left(\frac{-1}{15}-\frac{1}{6}\right)+\frac{3}{5}:\left(\frac{-1}{3}-1\frac{1}{15}\right)\)
h) \(10.\sqrt{0,01}.\sqrt{\frac{16}{9}+3\sqrt{49}-\frac{1}{6}\sqrt{4}}\)
i) \(\frac{2^4.2^6}{\left(2^5\right)^2}-\frac{2^5.15^3}{6^3.10^2}\)
k) \((2\frac{1}{3}+3\frac{1}{2}):\left(-4\frac{1}{6}+3\frac{1}{7}\right)+7\frac{1}{2}\)
n) \(4\frac{25}{16}+25\left(\frac{9}{16}:\frac{125}{64}\right):\frac{-27}{8}\)
m) \([1,5+2\frac{1}{2}-\left(2\sqrt{2}\right)^2]:[4\frac{1}{2}-\sqrt{1,96}+0,9]\)
o) \(\frac{5}{21}.\left(4\frac{1}{5}.7\frac{3}{4}+5\frac{1}{4}.4,2\right)\)
p) \(\left(\frac{2}{5}+\frac{2}{7}-\frac{2}{11}\right):\left(\frac{3}{7}-\frac{3}{11}+\frac{3}{5}\right)\)
Làm nhanh làm đúng mình Tick nha :))
\(B=\frac{2^3}{3.5}+\frac{2^3}{5.7}+\frac{2^3}{7.9}+......+\frac{2^3}{101.103}\)
\(B=\frac{2^3}{3.5}+\frac{2^3}{5.7}+....+\frac{2^3}{101.103}\)
\(\Rightarrow\frac{1}{2^2}.B=\frac{2}{3.5}+\frac{2}{4.7}+....+\frac{2}{101.103}\)
\(\Rightarrow\frac{1}{4}.B=\frac{1}{3}-\frac{1}{5}+\frac{1}{5}-\frac{1}{7}+...+\frac{1}{101}-\frac{1}{103}\)
\(\Rightarrow\frac{1}{4}.B=\frac{1}{3}-\frac{1}{103}=\frac{100}{309}\)
\(\Rightarrow B=\frac{100}{309}:\frac{1}{4}=\frac{400}{309}\)
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\(=2^2\left(\frac{2}{3.5}+\frac{2}{5.7}+\frac{2}{7.9}+...+\frac{2}{101.103}\right)\)
\(=4\left(\frac{1}{3}-\frac{1}{5}+\frac{1}{5}-\frac{1}{7}+\frac{1}{7}-\frac{1}{9}+...+\frac{1}{101}-\frac{1}{103}\right)\)
\(=4\left(\frac{1}{3}-\frac{1}{103}\right)\)
\(=4\cdot\frac{100}{309}=\frac{400}{309}\)
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Bài 1: Thực hiện phép tính:a, 3frac{1}{2}-frac{1}{2}.left(-4,25-frac{3}{4}right)^2:frac{5}{4}b, frac{3}{7}.1frac{1}{2}+frac{3}{7}.0,5-frac{3}{7}.9c, frac{125^{2016}.8^{2017}}{50^{2017}.20^{2018}}d, frac{4^{2002}.9^{1001}}{16^{1001}.3^{2003}}e, sqrt{25-16}-left|-3,7+0,7right|Bài 2: Tìm xa, frac{1}{3}x+frac{4}{5}3frac{4}{5}b, left|x+frac{3}{4}right|-2,251frac{3}{4}c, left(-x+frac{2}{5}right)^4frac{1}{16}d, left(frac{2}{5}right)^{3x}:left(frac{4}{3}right)^{21}left(frac{6}{20}right)^{21}e, frac{-x}{...
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Bài 1: Thực hiện phép tính:
a, \(3\frac{1}{2}-\frac{1}{2}.\left(-4,25-\frac{3}{4}\right)^2:\frac{5}{4}\)
b, \(\frac{3}{7}.1\frac{1}{2}+\frac{3}{7}.0,5-\frac{3}{7}.9\)
c, \(\frac{125^{2016}.8^{2017}}{50^{2017}.20^{2018}}\)
d, \(\frac{4^{2002}.9^{1001}}{16^{1001}.3^{2003}}\)
e, \(\sqrt{25-16}-\left|-3,7+0,7\right|\)
Bài 2: Tìm x
a, \(\frac{1}{3}x+\frac{4}{5}=3\frac{4}{5}\)
b, \(\left|x+\frac{3}{4}\right|-2,25=1\frac{3}{4}\)
c, \(\left(-x+\frac{2}{5}\right)^4=\frac{1}{16}\)
d, \(\left(\frac{2}{5}\right)^{3x}:\left(\frac{4}{3}\right)^{21}=\left(\frac{6}{20}\right)^{21}\)
e, \(\frac{-x}{\frac{3}{5}}=\frac{\frac{27}{5}}{-x}\)
g, \(x:1\frac{1}{2}=-2,5:2\frac{1}{5}\)
\(3\frac{1}{2}-\frac{1}{2}.\left(-4,25-\frac{3}{4}\right)^2:\frac{5}{4}\)
\(=\frac{7}{2}-\frac{1}{2}.\left(-4,25-0,75\right)^2:\frac{5}{4}\)
\(=\frac{7}{2}-\frac{1}{2}.\left(-5\right)^2:\frac{5}{4}\)
\(=\frac{7}{2}-\frac{1}{2}.5.\frac{4}{5}\)
\(=\frac{7}{2}-2\)
\(=\frac{7}{2}-\frac{4}{2}\)
\(=\frac{3}{2}\)
\(\frac{3}{7}.1\frac{1}{2}+\frac{3}{7}.0,5-\frac{3}{7}.9\)
\(=\frac{3}{7}.\left(\frac{3}{2}+\frac{1}{2}-9\right)\)
\(=\frac{3}{7}.\left(2-9\right)\)
\(=\frac{3}{7}.\left(-7\right)\)
\(=-3\)
\(\frac{125^{2016}.8^{2017}}{50^{2017}.20^{2018}}=\frac{\left(5^3\right)^{2016}.\left(2^3\right)^{2017}}{\left(5^2\right)^{2017}.2^{2017}.\left(2^2\right)^{2018}.5^{2018}}=\frac{\left(5^3\right)^{2016}.\left(2^3\right)^{2017}}{\left(5^3\right)^{2017}.\left(2^3\right)^{2017}.2.5}=\frac{1}{5^4.2}=\frac{1}{1250}\)( tính nhẩm, ko chắc đúng )
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1
a) \(3\frac{1}{2}-\frac{1}{2}\cdot\left(-4,25-\frac{3}{4}\right)^2\) : \(\frac{5}{4}\)
= \(3\cdot25:\frac{5}{4}\)
= \(3\cdot\left(25:\frac{5}{4}\right)\)
=\(3\cdot20\)
=60
b)=\(\frac{3}{7}\cdot\left(1\frac{1}{2}+0,5-9\right)\)
=\(\frac{3}{7}\cdot\left(-7\right)\)
=\(-3\)
c) =
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