1/2x5/5
1/2x5/5
\(\frac{1}{2}x\frac{5}{5}=\frac{1}{2}x1=\frac{1}{2}\)
1/2x5/5
\(\frac{1}{2}x\frac{5}{5}=\frac{1}{2}x1=\frac{1}{2}\)
duyệt đi
1/1x2+3/2x5+5/5x10+4/10x14+6/14x20
A = \(\dfrac{1}{1\times2}\) + \(\dfrac{3}{2\times5}\) + \(\dfrac{5}{5\times10}\) + \(\dfrac{4}{10\times14}\) + \(\dfrac{6}{14\times20}\)
A = \(\dfrac{1}{1}\) - \(\dfrac{1}{2}\) + \(\dfrac{1}{2}\) - \(\dfrac{1}{5}\) + \(\dfrac{1}{5}\) - \(\dfrac{1}{10}\) + \(\dfrac{1}{10}\) - \(\dfrac{1}{14}\) + \(\dfrac{1}{14}\) - \(\dfrac{1}{20}\)
A = \(\dfrac{1}{1}\) - \(\dfrac{1}{20}\)
A = \(\dfrac{19}{20}\)
3/5^2x5^2-2 1/4^3 :3/4^3 + 1/2
6 x5/3 7:8/4+1/3 2x5/8-1/2 3/7:5/6x1/4
10
\(\dfrac{23}{6}\)
\(\dfrac{3}{4}\)
\(\dfrac{9}{70}\)
6 x5/3=10 7:8/4+1/3=23/6 2x5/8-1/2=3/4 3/7:5/6x1/4=9/70
Tính nhanh:
a)1/3+2/3+5/12+4/3+1/12 b)3x5/6+5/6+2x5/6
c)___112x113+112x113_________
224x226+224x226
Tìm x, biết rằng:
a) 5 8 x + 2 5 = 1 5
b) 5 7 : x + 11 7 = 18 7
c) 2 x 5 − 1 : − 5 = 1 7
a)
5 8 x + 2 5 = 1 5 5 8 x = 1 5 − 2 5 5 8 x = − 1 5 x = − 1 5 : 5 8 x = − 1 5 . 8 5 x = − 8 25
b)
5 7 : x + 11 7 = 18 7 5 7 : x = 18 7 − 11 7 5 7 : x = 1 x = 5 7 : 1 x = 5 7
c)
2 x 5 − 1 : − 5 = 1 7 2 x 5 − 1 = 1 7 . − 5 2 x 5 − 1 = − 5 7 2 x 5 = − 5 7 + 1 2 x 5 = 2 5 x = 2 5 : 2 5 x = 1
Tìm x, biết rằng:
a) 5 8 x + 2 5 = 1 5
b) 5 7 : x + 11 7 = 18 7
c) 2 x 5 − 1 : − 5 = 1 7
a)
5 8 x + 2 5 = 1 5 5 8 x = 1 5 − 2 5 5 8 x = − 1 5 x = − 1 5 : 5 8 x = − 1 5 . 8 5 x = − 8 25
b)
5 7 : x + 11 7 = 18 7 5 7 : x = 18 7 − 11 7 5 7 : x = 1 x = 5 7 : 1 x = 5 7
c)
2 x 5 − 1 : − 5 = 1 7 2 x 5 − 1 = 1 7 . − 5 2 x 5 − 1 = − 5 7 2 x 5 = − 5 7 + 1 2 x 5 = 2 5 x = 2 5 : 2 5 x = 1
a,\(\frac{5}{8}x+\frac{2}{5}=\frac{1}{5}\)
\(< =>\frac{5}{8}x=\frac{1}{5}-\frac{2}{5}\)
\(< =>\frac{5}{8}x=-\frac{1}{5}\)
\(< =>x=-\frac{1}{5}:\frac{5}{8}=-\frac{8}{25}\)
\(\frac{5}{7}:x+\frac{11}{7}=\frac{18}{7}\)
\(< =>\frac{5}{7}.\frac{1}{x}=\frac{18}{7}-\frac{11}{7}\)
\(< =>\frac{5}{7x}=\frac{7}{7}=1\)
\(< =>7x=5< =>x=\frac{5}{7}\)
(2x+1)^3-5^4:5^2+1=2x5^2+1(^ là mũ, x thứ nhất là /íc/; x thứ hai là nhân, nhớ giải chi tiết)