Tính nhanh:
\(\frac{26\times1080-65\times2\times6\times4}{32-28+24-20+16-12+8-4}\)
tính nhanh: \(\frac{1\times3\times2\times4\times3\times5\times4\times6\times5\times7}{2\times2\times3\times3\times4\times4\times5\times5\times6\times6}\)
\(y=\frac{1\times2\times3+2\times4\times6+4\times8\times12+8\times16\times24}{2\times3\times4+4\times6\times8+8\times12\times16+16\times24\times32}\frac{ }{ }\)
\(y=\frac{1x2x3+2x4x6+4x8x12+8x16x24}{2x3x4+4x6x8+8x12x16+16x24x32}\)
\(y=\frac{1}{4}\)
tích nha . Đúng 100% luôn.
Tính nhanh:\(\frac{1\times2\times3+2\times4\times6+3\times6\times9+4\times8\times12+5\times10\times15}{1\times3\times5+2\times6\times10+3\times9\times15+4\times12\times20+5\times15\times25}-\frac{1+2+3+2+4+6+3+6+9+4+8+12+5+10+15}{1+3+5+2+6+10+3+9+15+4+12+20+5+15+25}\)
Tính giá trị các biểu thức sau 1 cách hợp lý:
a) A= 2018.20172017-2017.20182018
b) \(\frac{423134\times846267-423133}{423133\times846267+423134}\)
c) B= \(\frac{135\times1420+45\times780\times3}{3+6+9+12+...+24+27}\)
d) C= \(\frac{24347\times78-26\times4\times3\times6000}{4+5+6+7+...+24+25+28}\)
e) \(\frac{1978\times1979+1980\times21+1958}{1980\times1979-1978\times1979}\)
f) \(\left(12\times194+6\times437\times2+3\times369\times4\right)\div\left(1+5+9+13+...+57+61+65\times2-26\right)\)
Giusp m với. Tìm số A biết. 121:A dư 10, 61 : A dư 10. giải thích cách làm theo lớp 6 b nhé.Thank
tính :\(\frac{1}{1\times2\times3}+\frac{1}{2\times3\times4}+\frac{1}{3\times4\times5}+\frac{1}{4\times5\times6}+\frac{1}{5\times6\times7}+\frac{1}{6\times7\times8}+\frac{1}{7\times8\times9}+\frac{1}{8\times9\times10}\)
\(\frac{1}{1.2.3}+\frac{1}{2.3.4}+...+\frac{1}{8.9.10}=\frac{1}{2}.\left(\frac{1}{1.2}-\frac{1}{2.3}\right)+\frac{1}{2}.\left(\frac{1}{2.3}-\frac{1}{3.4}\right)+...+\frac{1}{2}.\left(\frac{1}{8.9}-\frac{1}{9.10}\right)\)
\(=\frac{1}{2}.\left(\frac{1}{1.2}-\frac{1}{2.3}+\frac{1}{2.3}-\frac{1}{3.4}+...+\frac{1}{8.9}-\frac{1}{9.10}\right)\)
\(\frac{1}{2}.\left(\frac{1}{1.2}-\frac{1}{9.10}\right)=\frac{1}{2}.\frac{22}{45}=\frac{11}{45}\)
Tính
\(\frac{5\times4^{15}-9^9-4\times3^{20}\times8^9}{5\times2^9\times6^{19}-7\times2^{29}\times27^6}\)
\(\frac{5\times4^{15}-9^9-4\times3^{20}\times8^9}{5\times2^9\times6^{19}-7\times2^{29}\times27^6}\)
\(=\frac{2^{29}\times3^{18}\times\left(2\times5-3\right)}{2^{28}\times3^{18}\times\left(5\times3-7\times2\right)}=2\)
tính \(\frac{2012.2013-1}{2012^2+2011}\)
Tính S = \(\frac{5\times2^{30}\times6^2\times3^{15}-2^3\times8^9\times3^{17}\times21}{21\times2^{29}\times3^{16}\times4-2^{29}\times\left(3^4\right)^5}\)
Ta có : S = \(\frac{5.2^{30}.6^3.3^{15}-2^3.8^9.3^{17}.21}{21.2^{29}.3^{16}.4-2^{29}.\left(3^4\right)^5}=\frac{5.2^{30}.\left(2.3\right)^3.3^{15}-2^3.\left(2^3\right)^9.3^{17}.3.7}{3.7.2^{29}.3^{16}.2^2-2^{29}.3^{20}}=\frac{5.2^{33}.3^{18}-2^{30}.3^{18}.7}{3^{17}.7.2^{31}-2^{29}.3^{20}}\)
\(=\frac{2^{30}.3^{18}.\left(5.2^3-7\right)}{3^{17}.2^{29}.\left(7.2^2-3^3\right)}=2.3.33=198\)
Tính:
\(\frac{5\times4^{15}-9^9-4\times3^{20}\times8^9}{5\times2^9\times6^{19}-7\times2^{29}\times27^6}\)
Trình bày luôn nhé mình đang vội !
\(\frac{72+36\times2+24\times3+18\times4+12\times6+168}{2+2+4+6+...+512+1024}\)
Các bạn giúp mình và ghi đầy đủ cách giải nhé !