Bai: Tim x bang cach hop ly :
a)\(\frac{-5}{1,2}=\frac{x}{-4,8}\)
b) \((\frac{x}{5})^2=\frac{9}{25}\)
bai: Thuc hien phep tinh bang cach hop ly nhat:
a) \((\frac{1}{5}-\frac{1}{4})^2\)
b) \((\frac{5}{3}+\frac{1}{2}):\frac{-13}{5}+1\frac{5}{6}\)
c) \((\frac{3}{17})^4.(\frac{-17}{6})^4\)
a, \(\left(\frac{1}{5}-\frac{1}{4}\right)^2=\left(\frac{-1}{20}\right)^2=\frac{1}{400}\)
b, \(\left(\frac{5}{3}+\frac{1}{2}\right):\frac{-13}{5}+1\frac{5}{6}\)
=> \(\frac{13}{6}:\frac{-13}{5}+\frac{11}{6}\)
=> \(\frac{13}{6}.\frac{5}{-13}+\frac{11}{6}\)
=> \(\frac{-5}{6}+\frac{11}{6}=\frac{6}{6}=1\)
c, \(\left(\frac{3}{17}\right)^4.\left(\frac{-17}{6}\right)^4\)
=> \(\left(\frac{3}{17}.\frac{-17}{6}\right)^4=\left(\frac{-1}{2}\right)^4=\frac{1}{16}\)
a) \(\left(\frac{1}{5}-\frac{1}{4}\right)^2=\left(-\frac{1}{20}\right)^2=\frac{1}{400}.\)
b) \(\left(\frac{5}{3}+\frac{1}{2}\right):-\frac{13}{5}+1\frac{5}{6}\)
= \(\frac{13}{6}:\left(-\frac{13}{5}\right)+\frac{11}{6}\)
= \(\left(-\frac{5}{6}\right)+\frac{11}{6}\)
= \(1.\)
c) \(\left(\frac{3}{17}\right)^4.\left(-\frac{17}{6}\right)^4\)
= \(\left[\frac{3}{17}.\left(-\frac{17}{6}\right)\right]^4\)
= \(\left(-\frac{1}{2}\right)^4=\frac{1}{16}.\)
Chúc bạn học tốt!
Tinh bang cach hop ly
\(\frac{-3}{31}+\frac{-6}{17}+\frac{1}{25}+\) \(\frac{-28}{31}+\frac{-11}{17}+\frac{-1}{5}\)
\(\frac{\frac{1}{9}-\frac{5}{6}-4}{\frac{7}{12}-\frac{1}{36}-10}\)
\(\frac{\frac{1}{9}-\frac{5}{6}-4}{\frac{7}{12}-\frac{1}{36}-10}=\frac{36.\left(\frac{1}{9}-\frac{5}{6}-4\right)}{36.\left(\frac{7}{12}-\frac{1}{36}-10\right)}\)
\(=\frac{4-6.5-36.4}{3.7-1-36.10}\)
\(=\frac{4-30-144}{21-1-360}\)
\(=\frac{-26-144}{20-360}=\frac{-170}{-340}=\frac{1}{2}\)
\(\frac{\frac{4}{36}-\frac{30}{36}-\frac{144}{36}}{\frac{21}{36}-\frac{1}{36}-\frac{360}{36}}=\frac{\frac{-170}{36}}{\frac{-340}{36}}=\frac{-170}{36}:\frac{-340}{36}=\frac{-170}{36}.\frac{36}{-340}=\frac{-170}{-340}=\frac{1}{2}\)
a, \(\frac{\frac{7}{12}+\frac{5}{6}-1}{5-\frac{3}{4}+\frac{1}{3}}\)
tinh theo cach hop ly :
M=1-\(\frac{5}{\sqrt{196}}-\frac{5}{\left(2\sqrt{21}\right)^2}-\frac{\sqrt{25}}{204}-\frac{\left(\sqrt{5}\right)^2}{374}\)
Tinh bang cach hop li
\(\frac{-3}{31}+\frac{-6}{17}+\frac{1}{25}+\)\(\frac{-28}{31}+\frac{-11}{17}+\frac{-1}{5}\)
âm 2( số -2) và 4/25
\(\frac{-3}{31}+\frac{-6}{17}+\frac{1}{25}+\frac{-28}{31}+\frac{-11}{17}+\frac{-1}{5}\)
\(=\left(\frac{-3}{31}+\frac{-28}{31}\right)+\left(\frac{-6}{17}+\frac{-11}{17}\right)+\left(\frac{1}{25}+\frac{-1}{5}\right)\)
\(=\frac{-31}{31}+\frac{-17}{17}+\frac{-4}{25}\)
\(=\left(-1\right)+\left(-1\right)+\frac{-4}{25}\)
\(=\frac{\left(-25\right)+\left(-25\right)+\left(-4\right)}{25}\)
\(=\frac{-54}{25}\)
(-3/31+-28/31)+(6/17+11/17)+1/25+-1/5
-1+-1+1/25 +-1/5
-2+1/25+-1/5
-2/1+1/25+-1/5
-50/25+1/25+-5/25
-49/25+-5/25
-54/25
mik đúng mn k cho mik nha cảm ơn mn
Bai 1:Tim x
a\(\frac{1}{9}=\frac{x}{27}\) b \(\frac{4}{x}=\frac{8}{6}\) c\(\frac{x}{3}-\frac{1}{2}=\frac{1}{5}\)
a) \(\frac{1}{9}=\frac{x}{27}\)
\(\Rightarrow x=\frac{1}{9}\cdot27\)
\(\Rightarrow x=3\)
b) \(\frac{4}{x}=\frac{8}{6}\)
\(\Rightarrow x=4:\frac{8}{6}\)
\(\Rightarrow x=3\)
c) \(\frac{x}{3}-\frac{1}{2}=\frac{1}{5}\)
\(\Rightarrow\frac{x}{3}=\frac{1}{5}+\frac{1}{2}\)
\(\Rightarrow x=\frac{7}{10}\cdot3\)
\(\Rightarrow x=\frac{21}{10}=2,1\)
\(a,\frac{1}{9}\)=\(\frac{3}{27}\)
\(b,\frac{4}{3}\)=\(\frac{8}{6}\)
\(c,\frac{x}{3}\)-\(\frac{1}{2}=\frac{1}{5}\)
\(\frac{x}{3}=\frac{1}{5}+\frac{1}{2}\)
\(\frac{x}{3}=\frac{7}{10}\)
\(\)
tim x biet:
\(\frac{x-5}{1990}+\frac{x-15}{1980}+\frac{x-25}{1970}=\frac{x-1990}{5}+\frac{x-1980}{15}+\frac{x-1970}{25}\)
trinh bay cach giai ho minh nhe
co gi ko hieu thi vao cho"doc them"
tìm giá trị x,y nhỏ nhất của biểu thức
A=l x - 1,3 l - 4,8 + l y - 4 l
tim x
30% của x bằng \(3\frac{1}{5}\)
\(\frac{2}{7}\)cua x bang \(\frac{36}{5}\)