tính
\(\dfrac{10^2\cdot5^3}{8\cdot25^2}\)
\(x=\frac{2^3\cdot25^2}{10^2\cdot5^3}\)
\(x=\frac{2^3\cdot25^2}{10^2\cdot5^3}=\frac{2^3\cdot\left(5^2\right)^2}{\left(2\cdot5\right)^2\cdot5^3}\)
\(=\frac{2^3\cdot5^4}{2^2\cdot5^2\cdot5^3}=\frac{2^3\cdot5^4}{2^2\cdot5^5}=\frac{2}{5}\)
Vậy x = 2/5
x=2^3.25^2/10^2.5^3
x=8.625/100.125
x=5000/12500
x=10/25
x=0,4
\(x=\frac{2^3.25^2}{10^2.5^3}=\frac{2^3.5^4}{2^2.5^2.5^3}=\frac{2^3.5^4}{2^2.5^5}\)\(=\frac{2}{5}\)
Tính nhanh
A=\(\frac{1\cdot5\cdot6+2\cdot10\cdot12+3\cdot15\cdot18+4\cdot20\cdot24+5\cdot25\cdot30}{1\cdot3\cdot5+2\cdot6\cdot10+3\cdot9\cdot15+4\cdot12\cdot20+5\cdot15\cdot25}\)
A=1.5.(3.2)+2.10.(6.2)+3.15.(9.2)+4.20.(12.2)+5.25.(15.2)
1.3.5+2.6.10+3.9.15+4.12.20+5.15.25
A=1.5.3+2.10.6+3.15.9+4.20.12+5.25.15(2.2.2.2.2)
1.3.5+2.6.10+3.9.15+4.12.20+5.15.25
A=2.2.2.2.2
A=32
\(\frac{1\cdot3\cdot5\cdot2+2\cdot10\cdot6\cdot2+3\cdot15\cdot9\cdot2+4\cdot20\cdot12\cdot2+5\cdot25\cdot15\cdot2}{1\cdot3\cdot5+2\cdot10\cdot6+3\cdot15\cdot9+4\cdot20\cdot12+5\cdot25\cdot15 }\)
\(2\cdot2\cdot2\cdot2\cdot2=2^5\)
\(=32\)
làm bừa thui,ai trên 11 điểm tích mình mình tích lại
Số số hạng là :
Có số cặp là :
50 : 2 = 25 ( cặp )
Mỗi cặp có giá trị là :
99 - 97 = 2
Tổng dãy trên là :
25 x 2 = 50
Đáp số : 50
Rút gọn :\(\frac{2\cdot3\cdot5+4\cdot9\cdot25+6\cdot9\cdot35+10\cdot21\cdot40}{2\cdot3\cdot5+4\cdot9\cdot35+6\cdot9\cdot49+10\cdot21\cdot56}\)
1)Thực hiện phép tính
a) \(\dfrac{9^8\cdot5^6}{3^7\cdot27^3\cdot25^4}\) b) \(\dfrac{5^{20}\cdot6^{18}}{15^{20}\cdot4^{10}}\) c) \(\left(\dfrac{1}{3}\right)^{50}\cdot9^{25}-\left(\dfrac{2}{3}\right)^{100}:\left(\dfrac{8}{27}\right)^{33}\) d) \(\left(\dfrac{3}{8}\right)^{60}\cdot\left(\dfrac{2}{3}\right)^{60}:\left(\dfrac{1}{2}\right)^{119}\cdot\left(\dfrac{1}{2}\right)\)
2) Tìm x, biết:
a) \(\dfrac{x}{12}=\dfrac{5}{x}\) b)\(8^x=2^{2x+3}\) c)\(\dfrac{1}{2}\sqrt{\dfrac{1}{2}x-2}-\dfrac{2}{3}=\dfrac{1}{3}\)
Bài 2:
a: =>x^2=60
=>\(x=\pm2\sqrt{15}\)
b: =>2^2x+3=2^3x
=>3x=2x+3
=>x=3
c: \(\Leftrightarrow\sqrt{\dfrac{1}{2}x-2}\cdot\dfrac{1}{2}=1\)
\(\Leftrightarrow\sqrt{\dfrac{1}{2}x-2}=2\)
=>1/2x-2=4
=>1/2x=6
=>x=12
1)Tính
a.\(\frac{3^6\cdot45^4-15^{13}\cdot5^{-9}}{27^4\cdot25^3+45^6}\)
b.\(\frac{\left(\frac{2}{5}\right)^7\cdot5^7+\left(\frac{9}{4}\right)^3\div\left(\frac{3}{16}\right)^3}{2^7\cdot5^2+512}\)
\(A=\frac{1.5\cdot6+2\cdot10\cdot12+3\cdot15\cdot18+4\cdot20\cdot24+5\cdot25\cdot30}{1\cdot3\cdot5+2\cdot6\cdot10+3\cdot9\cdot15+4\cdot12\cdot20+5\cdot15\cdot25}\)
=\(\frac{30\left(1+8+27+64+125\right)}{5\left(3+24+81+64+375\right)}\)
= \(\frac{30.225}{5.574}\)
=\(\frac{6750}{2870}\)
=\(\frac{675}{287}\)
K mình với!!!!
a)\(\dfrac{8}{5}\cdot\dfrac{2}{3}+\dfrac{-5\cdot5}{3\cdot5}\)
b) \(\dfrac{6}{7}+\dfrac{5}{8}:5-\dfrac{3}{16}\left(-2\right)^2\)
`8/5 .2/3 + (-5.5)/(3.5) = 16/15 - 5/3 = -3/5`
b) 6/7+5/8 :5 -3/16 .(-2)^2=6/7 + 1/8 - 3/16 .4`
`=55/56 - 3/4`
`=13/56`
\(a,\dfrac{8}{5}.\dfrac{2}{3}+\dfrac{-5.5}{3.5}=\dfrac{16}{15}+\dfrac{-25}{15}=-\dfrac{9}{15}=-\dfrac{3}{5}\)
\(b,\dfrac{6}{7}+\dfrac{5}{8}:5-\dfrac{3}{16}\left(-2\right)^2=\dfrac{6}{7}+\dfrac{5}{8}:5-\dfrac{3}{16}.4=\dfrac{6}{7}+\dfrac{1}{8}-\dfrac{3}{4}=\dfrac{55}{56}-\dfrac{3}{4}=\dfrac{13}{56}\)
Tính nhanh:
\(\dfrac{3}{2\cdot5}\)+\(\dfrac{3}{5\cdot8}\)+\(\dfrac{3}{8\cdot11}\)+\(\dfrac{3}{11\cdot14}\)
`# \text {Ryo}`
\(\dfrac{3}{2\cdot5}+\dfrac{3}{5\cdot8}+\dfrac{3}{8\cdot11}+\dfrac{3}{11\cdot14}\\ =\dfrac{1}{2}-\dfrac{1}{5}+\dfrac{1}{5}-\dfrac{1}{8}+\dfrac{1}{8}-\dfrac{1}{11}+\dfrac{1}{11}-\dfrac{1}{14}\\ =\dfrac{1}{2}-\left(\dfrac{1}{5}-\dfrac{1}{5}\right)-\left(\dfrac{1}{8}-\dfrac{1}{8}\right)-\left(\dfrac{1}{11}-\dfrac{1}{11}\right)-\dfrac{1}{14}\\ =\dfrac{1}{2}-\dfrac{1}{14}\\ =\dfrac{7}{14}-\dfrac{1}{14}\\ =\dfrac{6}{14}\\ =\dfrac{3}{7}\)
\(1-\frac{3}{2\cdot10}-\frac{3}{4\cdot5}-\frac{3}{6\cdot20}-\frac{3}{8\cdot25}-...-\frac{3}{198\cdot500}\)