\(3-\left(-\frac{6}{7}\right)^0+\left(\frac{1}{2}\right)^2:2\) ai nhanh mình tick cho
\(3-\left(-\frac{6}{7}\right)^0+\left(\frac{1}{2}\right)^2:2\) ai nhanh nhất mình tick cho
\(=3-1+\frac{1}{2^2.2}\)
\(=2+\frac{1}{8}=\frac{17}{8}\)
\(3-\left(\frac{-6}{7}\right)^0+\left(\frac{1}{2}\right)^2:2\)
\(=3-1+\frac{1}{4}:2\)
\(=3-1+\frac{1}{8}\)
\(=4+\frac{1}{8}\)
\(=\frac{32}{8}+\frac{1}{8}\)
\(=\frac{33}{8}\)
6.Tính nhanh : \(\frac{22}{7}-2\frac{1}{7}-\left(1-\frac{1}{2}\right)\times\left(1-\frac{1}{3}\right)\times...\times\left(1-\frac{1}{2015}\right)\)\(\times\left(1-\frac{1}{2016}\right)\) Ai giúp mình với làm nhanh và đúng mình tick cho nhé
5) Tính
a) \(4.\left(1\frac{1}{4}\right)^2+25.[\left(\frac{3}{4}\right)^2:\left(\frac{5}{4}\right)^3]:\left(\frac{3}{2}\right)^3\)
b) \(3-\left(\frac{-6}{7}\right)^0+\left(\frac{1}{2}\right)^2:2\)
MK CẦN GẤP Ạ , AI NHANH MK TICK NHÉ , CẢM ƠN TRƯỚC
1 +\(\frac{1}{2}\left(1+2\right)+\frac{1}{3}\left(1+2+3\right)+\frac{1}{4}+\left(1+2+3+4\right)+...+\frac{1}{20}\left(1+2+3+4+.....+20\right)\)
giúp mình với ai nhanh mình tick cho
Giai phương trình : \(\left(\frac{x-1}{x+2}\right)^2-4\left(\frac{x^2-1}{x^2-4}\right)^2+3\left(\frac{x+1}{x-2}\right)^2=0\)0
Ai làm nhanh và đúng nhất thì mình sẽ TICK cho
\(\left(\frac{x-1}{x+2}\right)^2-4\left(\frac{x^2-1}{x^2-4}\right)^2+3\left(\frac{x+1}{x-2}\right)^2=0\left(1\right)\)
\(ĐKXĐ:x\ne\pm2\)
Đặt \(\frac{x-1}{x+2}=a;\frac{x+1}{x-2}=b\)
=> Phương trình (1) <=> \(a^2-4ab+3b^2=0\)
\(\Leftrightarrow a^2-3ab-ab+3b^2=0\)
\(\Leftrightarrow a\left(a-b\right)-3b\left(a-b\right)=0\)
\(\Leftrightarrow\left(a-3b\right)\left(a-b\right)=0\)
\(\Leftrightarrow\left(a-3b\right)\left(a-b\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}a-3b=0\\a-b=0\end{cases}\Leftrightarrow\orbr{\begin{cases}a=3b\\a=b\end{cases}}}\)
=> \(b=0;a=0\)
Bạn cùng trường :">
a,\(x^3-\frac{4}{25}x=0\)
b,\(\left(\frac{3}{8}+\frac{-3}{4}+\frac{7}{12}\right):\frac{5}{6}+\frac{1}{2}\)
c\(4.\left(\frac{-1}{2}\right)^3-2.\left(\frac{-1}{2}\right)^2+3.\left(\frac{-1}{2}\right)-1.\left(\frac{-1}{2}\right)^0\)
AI GIAI DUOC MINH CHO 10 TICK
a) \(x^3-\frac{4}{25}x=0\)
\(\Leftrightarrow x\left(x+\frac{2}{5}\right)\left(x-\frac{2}{5}\right)=0\)
<=> x = 0
Xét 2 trường hợp:
\(\Leftrightarrow x+\frac{2}{5}=0\)
\(x=0-\frac{2}{5}\)
\(x=-\frac{2}{5}\)
\(\Leftrightarrow x-\frac{2}{5}=0\)
\(x=0+\frac{2}{5}\)
\(x=\frac{2}{5}\)
\(\Rightarrow\orbr{\begin{cases}x=0\\x=\pm\frac{2}{5}\end{cases}}\)
b) \(\left(\frac{3}{8}+\frac{-3}{4}+\frac{7}{12}\right):\frac{5}{6}+\frac{1}{2}\)
\(=\left(\frac{3}{8}+\frac{-3}{4}+\frac{7}{12}\right):\frac{4}{3}\)
\(=\frac{13}{40}:\frac{4}{3}\)
\(=\frac{39}{120}=\frac{13}{40}\)
c) \(4\left(\frac{-1}{2}\right)^3-2\left(\frac{-1}{2}\right)^2+3\left(\frac{-1}{2}\right)-1\left(\frac{-1}{2}\right)^0\)
\(=4\left(\frac{-1}{2}\right)^3-2\left(\frac{-1}{2}\right)^3+3\left(\frac{-1}{2}\right)-1.1\)
\(=-\frac{1}{2}-\frac{1}{2}-\frac{3}{2}-1.1\)
\(=-\frac{5}{2}-1\)
\(=-\frac{7}{2}\)
\(E=\left(1-\frac{1}{1+2}\right)\left(1-\frac{1}{1+2+3}\right)...\left(1-\frac{1}{1+2+3+...+2013}\right)\)
Ai nhanh mình tick cho!
ai giúp mình câu này với,mình tick cho
a)\(\left(-\frac{1}{2}\right)^2:\left(1\frac{5}{16}-\sqrt{4}+\frac{1}{2}\right)+2008^0\) b)\(7\frac{1}{6}:\left(-\sqrt{\frac{49}{36}}\right)+10\frac{5}{6}.\left(-\frac{14}{2^2.3}\right)+\left|-\frac{1}{2}\right|\)
c)\(\left(-\frac{1}{2}\right)^2+5\frac{1}{2}\left(4,5-\sqrt{\sqrt{16}}\right)+\frac{2^3}{-\left|-2\right|^2}\) d)\(\frac{4^2.8^6.9^{13}}{6^6.16^2.27}\)
a)
1/4:(31/16-2+1/2)+1
=1/4:(-1/16+1/2)+1
=(1/4:7/16)+1
=4/7+1
=11/7
b)
43/6:(-7/6)+65/6.(-7/6)+1/2
=-43/7+-455/36+1/2
=-4607/252
c)
1/4+11/2.5/2+-2
=23/4.5/2+-2
=115/8+-2
=99/8
d) bài 4 rất dễ bạn tự làm đi nhé
tick cho mk đi nhanh lên đó nhiên
=
Tính nhanh:
\(\frac{9,1+10,2+...+17,9+19}{\left(1-\frac{2}{42}\right)\cdot\left(1-\frac{2}{56}\right)\cdot...\cdot\left(1-\frac{2}{2550}\right)\cdot\left(1-\frac{2}{2652}\right)}\cdot\frac{265}{357}\)
Làm nhanh cho mình trước 14h30p 30/7/2016
Ai làm được cho 5 lần tick