1: =1/4+3/4=4/4=1
2: =1+4*2/5
=1+8/5
=13/5
3: =0,09+2/5-1/2
=0,09+0,4-0,5
=0,09-0,1
=-0,01
4: =2/7*14-1=4-1=3
5: =0,2+0,3*2
=0,2+0,6
=0,8
6: =3/8-1/2+1/3
=3/8-1/6
=9/24-4/24=5/24
7: =7/12-15/24
=14/24-15/24=-1/24
8: \(=-\dfrac{1}{3}\cdot\dfrac{6}{7}-\dfrac{13}{14}+1=-\dfrac{2}{7}-\dfrac{13}{14}+1=-\dfrac{2}{7}+\dfrac{1}{14}=\dfrac{-3}{14}\)
9: \(=\dfrac{1}{9}-6:\dfrac{1}{2}+5-1=\dfrac{1}{9}-12+4=\dfrac{1}{9}-8=-\dfrac{71}{9}\)
10: \(=\dfrac{9-10}{15}:\dfrac{1}{9}-20=-\dfrac{3}{5}-20=-20,6\)
Bài 1:
1)\(\dfrac{1}{4}+\left|-\dfrac{3}{4}\right|=\dfrac{1}{4}+\dfrac{3}{4}=1\)
2)\(1+4\cdot\left|-\dfrac{2}{5}\right|=1+4\cdot\dfrac{2}{5}=1+\dfrac{8}{5}=\dfrac{13}{5}\)
3)\(0,09+\left|-\dfrac{2}{5}\right|-\dfrac{1}{2}=\dfrac{9}{100}+\dfrac{2}{5}-\dfrac{1}{2}=\dfrac{9}{100}+\dfrac{40}{100}-\dfrac{50}{100}=-\dfrac{1}{100}\)
4)\(\left|-\dfrac{2}{7}\right|:\dfrac{1}{14}-1=\dfrac{2}{7}\cdot14-1=4-1=3\)
5)\(\left|-0,2\right|+\left|-0,3\right|\cdot2=0,2+0,6=0,8\)
6)\(\dfrac{3}{8}-\left|\dfrac{1}{3}-\dfrac{1}{2}\right|=\dfrac{3}{8}-\left|-\dfrac{1}{6}\right|=\dfrac{3}{8}-\dfrac{1}{6}=\dfrac{5}{24}\)
7)\(\dfrac{7}{12}-\left|-\dfrac{3}{4}\cdot\dfrac{5}{6}\right|=\dfrac{7}{12}-\dfrac{5}{8}=-\dfrac{1}{24}\)
8)\(\dfrac{-1^{2023}}{3}\cdot\dfrac{6}{7}-\left|\dfrac{1}{14}-1\right|+2022^0\)
\(=-\dfrac{1}{3}\cdot\dfrac{6}{7}-\dfrac{13}{14}+1\)
\(=-\dfrac{2}{7}-\dfrac{13}{14}+1\)
\(=-\dfrac{3}{14}\)
9)\(\left(-\dfrac{1}{3}\right)^2-6:\left|-\dfrac{1}{2}\right|+\sqrt{25}-2023^0\)
\(=\dfrac{1}{9}-12+5-1\)
\(=-\dfrac{71}{9}\)
10)\(\left(\dfrac{3}{5}-\dfrac{2}{3}\right):\left|-\dfrac{1}{9}\right|+\left(-20,23\right)^0\)
\(=-\dfrac{1}{15}\cdot9+1\)
\(=-\dfrac{3}{5}+1=\dfrac{2}{5}\)
#kễnh
1) \(\dfrac{1}{4}+\left|-\dfrac{3}{4}\right|=\dfrac{1}{4}+\dfrac{3}{4}=1\)
2) \(1+4\cdot\left|\dfrac{-2}{5}\right|=1+4\cdot\dfrac{2}{5}\)
\(=\dfrac{5}{5}+\dfrac{8}{5}=\dfrac{13}{5}\)
3) \(0,09+\left|-\dfrac{2}{5}\right|-\dfrac{1}{2}\)
\(=0,09+0,4-0,5\)
\(=-0,01\)
4) \(\left|\dfrac{-2}{7}\right|:\dfrac{1}{14}-1\)
\(=\dfrac{2}{7}\cdot14-1\)
\(=4-1\)
\(=3\)
5) \(\left|-0,2\right|+\left|-0,3\right|\cdot2\)
\(=0,2+0,3\cdot2\)
\(=0,2+0,6\)
\(=0,8\)
6) \(\dfrac{3}{8}-\left|\dfrac{1}{3}-\dfrac{1}{2}\right|\)
\(=\dfrac{3}{8}-\left|-\dfrac{1}{6}\right|\)
\(=\dfrac{3}{8}-\dfrac{1}{6}\)
\(=\dfrac{5}{24}\)
7) \(\dfrac{7}{12}-\left|\dfrac{-3}{4}\cdot\dfrac{5}{6}\right|\)
\(=\dfrac{7}{12}-\left|-\dfrac{5}{8}\right|\)
\(=\dfrac{7}{12}-\dfrac{5}{8}\)
\(=-\dfrac{1}{24}\)
8) \(\dfrac{-1^{2023}}{3}\cdot\dfrac{6}{7}-\left|\dfrac{1}{14}-1\right| +2022^0\)
\(=-\dfrac{1}{3}\cdot\dfrac{6}{7}-\left|-\dfrac{13}{14}\right|+1\)
\(=-\dfrac{2}{7}-\dfrac{13}{14}+1\)
\(=-\dfrac{4}{14}-\dfrac{13}{14}+\dfrac{14}{14}\)
\(=-\dfrac{3}{14}\)
9) \(\left(-\dfrac{1}{3}\right)^2-6:\left|\dfrac{-1}{2}\right|+\sqrt{25}-2023^0\)
\(=\dfrac{1}{9}-6:\dfrac{1}{2}+5-1\)
\(=\dfrac{1}{9}-12+4\)
\(=\dfrac{1}{9}-8\)
\(=-\dfrac{71}{9}\)
10) \(\left(\dfrac{3}{5}-\dfrac{2}{3}\right):\left|\dfrac{-1}{9}\right|+\left(-20,23\right)^0\)
\(=-\dfrac{1}{15}:\dfrac{1}{9}+1\)
\(=-\dfrac{3}{5}+\dfrac{5}{5}\)
\(=\dfrac{2}{5}\)
#Toru
\(a,\dfrac{1}{4}+\left|-\dfrac{3}{4}\right|\\ =\dfrac{1}{4}+\dfrac{3}{4}\\ =\dfrac{4}{4}=1\\ b,1+4\cdot\left|-\dfrac{2}{5}\right|\\ =1+4\cdot\dfrac{2}{5}\\ =1+\dfrac{8}{5}\\ =\dfrac{5}{5}+\dfrac{8}{5}\\ =\dfrac{13}{5}\\ c,0,09+\left|-\dfrac{2}{5}\right|-\dfrac{1}{2}\\ =0,09+0,4-0,5\\ =0,99\\ d,\left|-\dfrac{2}{7}\right|:\dfrac{1}{14}-1\\ =\dfrac{2}{7}:\dfrac{1}{14}-1\\ =\dfrac{2}{7}\cdot14-1\\ =\dfrac{28}{7}-1\\ =4-1=3\)
\(e,\left|-0,2\right|+\left|-0,3\right|\cdot2\\ =0,2+0,3\cdot2\\ =0,2+0,6\\ =0,8\)
\(g,\dfrac{3}{8}-\left|\dfrac{1}{3}-\dfrac{1}{2}\right|\\ =\dfrac{3}{8}-\left|\dfrac{2}{6}-\dfrac{3}{6}\right|\\ =\dfrac{3}{8}-\left|-\dfrac{1}{6}\right|\\ =\dfrac{3}{8}-\dfrac{1}{6}\\ =\dfrac{18}{48}-\dfrac{8}{48}\\ =\dfrac{10}{48}=\dfrac{5}{24}\)
\(h,\dfrac{7}{12}-\left|-\dfrac{3}{4}\cdot\dfrac{5}{6}\right|\\ =\dfrac{7}{12}-\left|-\dfrac{15}{24}\right|\\ =\dfrac{7}{12}-\dfrac{15}{24}\\ =\dfrac{14}{24}-\dfrac{15}{24}\\ =-\dfrac{1}{24}\)
\(i,\dfrac{-1^{2023}}{3}\cdot\dfrac{6}{7}-\left|\dfrac{1}{14}-1\right|+2022^0\\ =\dfrac{-1}{3}\cdot\dfrac{6}{7}-\left|\dfrac{1}{14}-\dfrac{14}{14}\right|+1\\ =-\dfrac{6}{21}-\dfrac{13}{14}+1\\ =-\dfrac{2}{7}-\dfrac{13}{14}+1\\ =-\dfrac{4}{14}-\dfrac{13}{14}+\dfrac{14}{14}\\=-\dfrac{3}{14}\)
\(k,\left(-\dfrac{1}{3}\right)^2-6:\left|-\dfrac{1}{2}\right|+\sqrt{25}-2023^0\\ =\dfrac{1}{9}-6:\dfrac{1}{2}+5-1\\ =\dfrac{1}{9}-12+5-1\\ =\dfrac{1}{9}-\dfrac{108}{9}+\dfrac{45}{9}-\dfrac{9}{9}\\ =-\dfrac{71}{9}\)
\(l,\left(\dfrac{3}{5}-\dfrac{2}{3}\right):\left|-\dfrac{1}{9}\right|+\left(-20,23\right)^0\\ =\left(\dfrac{9}{15}-\dfrac{10}{15}\right):\dfrac{1}{9}+1\\ =-\dfrac{1}{15}\cdot9+1\\ =-\dfrac{9}{15}+1\\ =-\dfrac{3}{5}+1\\ =-\dfrac{3}{5}+\dfrac{5}{5}\\ =\dfrac{2}{5}\)