1. tính nhanh
(\(\frac{1}{3}\)+\(\frac{12}{67}\)+\(\frac{13}{41}\)) - (\(\frac{79}{67}\)-\(\frac{28}{41}\))
2. tìm x
\(\frac{1}{2}\). x + \(\frac{2}{1.2.3}\)+ \(\frac{2}{2.3.4}\)+............+\(\frac{2}{98.99.100}\)
so sánh\(A=\frac{31}{13}-\left(\frac{7}{32}+\frac{8}{2}\right)vaB=\left(\frac{1}{3}+\frac{12}{67}+\frac{13}{41}\right)-\left(\frac{79}{67}-\frac{28}{41}\right)\)
Tính
\(\left(\frac{1}{3}+\frac{12}{67}+\frac{13}{41}\right)-\left(\frac{79}{67}-\frac{28}{41}\right)\)
\(\left(\frac{1}{3}+\frac{12}{67}+\frac{13}{41}\right)-\left(\frac{79}{67}-\frac{28}{41}\right)\)
\(=\frac{1}{3}+\frac{12}{67}+\frac{13}{41}-\frac{79}{67}-\frac{28}{41}\)
\(=\left(\frac{12}{67}-\frac{79}{67}\right)+\left(\frac{13}{41}+\frac{28}{41}\right)+\frac{1}{3}\)
\(=\left(-1\right)+1+\frac{1}{3}\)
\(=0+\frac{1}{3}\)
\(=\frac{1}{3}\)
=1/3+12/67+13/41-79/67+28/41
=1/3+(12/67-79/67)+(13/41+28/41)
=1/3+(-1)+1
=1/3+0
=1/3
\(\left(\frac{1}{3}+\frac{12}{67}+\frac{13}{41}\right)-\frac{79}{67}+\frac{28}{41}\)
\(\left(\frac{1}{3}+\frac{12}{67}+\frac{13}{41}\right)-\frac{79}{67}+\frac{28}{41}\) \(=\frac{1}{3}+\frac{12}{67}+\frac{13}{41}-\frac{79}{67}+\frac{28}{41}=\frac{1}{3}+\left(\frac{12}{67}-\frac{79}{67}\right)+\left(\frac{13}{41}+\frac{28}{41}\right)\) \(=\frac{1}{3}+\left(-1\right)+1=\frac{1}{3}\)
Chúc bạn hc giỏi ,Trần Phúc Đông❣ღ!
So sánh : A = \(\frac{31}{23}+\left(\frac{7}{23}+\frac{8}{2}\right)\)và B = \(\left(\frac{1}{3}+\frac{12}{67}+\frac{13}{41}\right)-\left(\frac{79}{67}+\frac{28}{41}\right)\)
\(\left(\frac{1}{3}+\frac{12}{67}+\frac{13}{41}\right)-\left(\frac{79}{67}-\frac{28}{41}\right)\)
\(\left(\frac{1}{3}+\frac{12}{67}+\frac{13}{41}\right)-\left(\frac{79}{67}-\frac{28}{41}\right)\)
=\(\frac{1}{3}+\frac{12}{67}+\frac{13}{41}-\frac{79}{67}+\frac{28}{41}\)
=\(\frac{1}{3}+\left(\frac{12}{67}-\frac{79}{67}\right)+\left(\frac{13}{41}+\frac{28}{41}\right)\)
=\(\frac{1}{3}+\left(\frac{-67}{67}\right)+\left(\frac{41}{41}\right)\)
=\(\frac{1}{3}-1+1\)
=\(\frac{1}{3}\)
\(\left(\frac{1}{3}+\frac{12}{67}+\frac{13}{41}\right)-\left(\frac{79}{67}-\frac{28}{41}\right)\)
=\(\frac{1}{3}+\frac{12}{67}+\frac{13}{41}-\frac{79}{67}+\frac{28}{41}\)
=\(\frac{1}{3}+\left(\frac{12}{67}-\frac{79}{67}\right)+\left(\frac{13}{41}+\frac{28}{41}\right)\)
=\(\frac{1}{3}+\left(\frac{-67}{67}\right)+\left(\frac{41}{41}\right)\)
=\(\frac{1}{3}-1+1\)
=\(\frac{1}{3}\)
\(\left(\frac{1}{3}+\frac{12}{67}+\frac{13}{41}\right)-\left(\frac{79}{67}-\frac{28}{41}\right)\)
\(=\frac{1}{3}+\frac{12}{67}+\frac{13}{41}-\frac{79}{67}+\frac{28}{41}\)
\(=\frac{1}{3}+\left(\frac{12}{67}-\frac{79}{67}\right)+\left(\frac{13}{41}+\frac{28}{41}\right)\)
\(=\frac{1}{3}+\left(-1\right)+1\)
\(=\frac{1}{3}+0\)
\(=\frac{1}{3}\)
_Chúc bạn học tốt_
Bài 1: Tính bằng cách hợp lí nhất.
a.\(\frac{1}{1.2}+\frac{1}{2.3}+...+\frac{1}{2006.2007}\)
b.\(\frac{30}{51}-\frac{20}{52}+\frac{14}{34}-\frac{56}{91}-2\)
c.\([\frac{1}{3}+\frac{12}{67}+\frac{13}{41}]-[\frac{79}{67}-\frac{28}{41}]\)
d.\(\frac{2}{15}+\frac{2}{35}+\frac{2}{63}+\frac{2}{99}+...+\frac{2}{399}\)
Ai nhanh mik tick 3 cái, mik dg cần gấp
so sánh: A= \(\frac{31}{23}-\left[\frac{7}{32}+\frac{8}{2}\right]\) và B=\(\left[\frac{1}{3}+\frac{12}{67}+\frac{13}{41}\right]-\left[\frac{79}{67}-\frac{28}{41}\right]\)
So sánh:
A = \(\frac{31}{23}-\left(\frac{7}{32}+\frac{8}{2}\right)\)và B = \(\left(\frac{1}{3}+\frac{12}{67}+\frac{13}{41}\right)-\left(\frac{79}{67}-\frac{28}{41}\right)\)
\(\frac{31}{23}-\left(\frac{7}{32}+\frac{8}{23}\right)+\left(\frac{1}{3}+\frac{12}{67}+\frac{13}{41}\right)-\left(\frac{79}{67}-\frac{28}{41}\right)\)
minh k biet xin loi ban nha!
minh k biet xin loi ban nha!
minh k biet xin loi ban nha!
minh k biet xin loi ban nha!