Rút gọn rồi tính: 146 , 5 2 - 109 , 5 2 + 27 . 256
rút gọn rồi tính
5/10-2/15 ; 5/20-1/6 ; 6/18+6/24
a, 5/10 - 2/15 = 1/2 - 2/15 = 15/30 - 4/30 = 11/30
b,5/20 - 1/6 = 1/4 - 1/6 = 3/12 - 2/12 = 1/12
c,6/18 - 6/24 = 1/3 - 1/4 = 4/12 - 3/12 = 1/12
d,5/9 - 3/12 = 5/9 - 1/4 = 20/36 - 9/36 = 11/36
chắc là đúng á , tại lớp 8 rồi ko nhớ lắm , mà vote mình nhá
Tính rồi rút gọn :
1/5 + 5/12
\(\dfrac{1}{5}+\dfrac{5}{12}=\dfrac{37}{60}\)
11/5+5/11 tính rồi rút gọn
\(\dfrac{11}{5}+\dfrac{5}{11}=\dfrac{11\times11+5\times5}{5\times11}=\dfrac{121+25}{55}=\dfrac{146}{55}\)
tính rồi rút gọn
3/5 + 1/2 - 7/10
4/7 : 8/11
\(\dfrac{3}{5}+\dfrac{1}{2}-\dfrac{7}{10}=\dfrac{6}{10}+\dfrac{5}{10}-\dfrac{7}{10}=\dfrac{11}{10}-\dfrac{7}{10}=\dfrac{4}{10}=\dfrac{2}{5}\)
\(\dfrac{4}{7}:\dfrac{8}{11}=\dfrac{4}{7}\times\dfrac{11}{8}=\dfrac{44}{56}=\dfrac{11}{14}\)
\(\dfrac{6}{10}+\dfrac{5}{10}-\dfrac{7}{10}=\dfrac{4}{10}=\dfrac{2}{5}\)
\(\dfrac{4}{7}x\dfrac{11}{8}=\dfrac{44}{56}=\dfrac{11}{14}\)
\(\dfrac{3}{5}+\dfrac{1}{2}-\dfrac{7}{10}=\dfrac{6}{10}+\dfrac{5}{10}-\dfrac{7}{10}=\dfrac{4}{10}=\dfrac{2}{5}\)
\(\dfrac{4}{7}:\dfrac{8}{11}=\dfrac{4}{7}\times\dfrac{11}{8}=\dfrac{44}{56}=\dfrac{11}{14}\)
Rút gọn rồi tính
A.4/5+3/15 B.2/3+32/24 C.5/6+15/18
a) \(\dfrac{4}{5}+\dfrac{3}{15}=\dfrac{4}{5}+\dfrac{1}{5}=\dfrac{5}{5}=1\)
b) \(\dfrac{2}{3}+\dfrac{32}{24}=\dfrac{2}{3}+\dfrac{4}{3}=\dfrac{6}{3}=2\)
c) \(\dfrac{5}{6}+\dfrac{15}{18}=\dfrac{5}{6}+\dfrac{5}{6}=\dfrac{10}{6}=\dfrac{5}{3}\).
Rút gọn rồi tính: \(a.\frac{16}{24}-\frac{1}{3}=\frac{2}{3}-\frac{1}{3}=\frac{1}{3}\)
\(b.\frac{4}{5}-\frac{12}{60}=\frac{4}{5}-\frac{1}{5}=\frac{3}{5}\)
Tính rồi rút gọn:
\(a.\frac{17}{6}-\frac{2}{6}=\frac{15}{6}\)
\(b.\frac{16}{15}-\frac{11}{15}=\frac{5}{15}=\frac{1}{3}\)
\(c.\frac{19}{12}-\frac{13}{12}=\frac{6}{12}=\frac{1}{2}\)
1a2/3-1/3=1/3 c4/5-1/5=3/5 tinh roi rut gon 17/6-2/6=15/6=5/2 16/15-11/15=5/15=1/3 19/12-13/12=6/12=1/2
chuc bn hoc tot
rút gọn rồi tính giá trị biể thứ:(x+3)(x-2)-(x-5)(x+5) tại x=2
\(A=\left(x+3\right)\left(x-2\right)-\left(x-5\right)\left(x+5\right)\)
\(=x\left(x-2\right)+3\left(x-2\right)+25-x^2\)
\(=x^2+x-6+25-x^2\)
\(=x+19\)
Tại \(x=2\)\(\Rightarrow A=2+19=21\)
Rút gọn rồi tính: 5 - 2 4
5 - 2 4 = 5 - 2 2 2 = 5 - 2 2 = 5 . 4 = 5 . 4 = 20
Tính rồi rút gọn 1/2 + 1/2 = 3/8 + 1/8 7/9+ 5/9
Lời giải:
$\frac{1}{2}+\frac{1}{2}=\frac{1+1}{2}=\frac{2}{2}=1$
$\frac{3}{8}+\frac{1}{8}=\frac{3+1}{8}=\frac{4}{8}=\frac{1}{2}$
$\frac{7}{9}+\frac{5}{9}=\frac{7+5}{9}=\frac{12}{9}=\frac{3\times 4}{3\times 3}=\frac{4}{3}$
bài 1 rút gọn rồi tính
a. 2/8+5/6
a, =1/4 + 5/6
=3/12 + 10/12
=13/12
\(\frac{2}{8}\)+\(\frac{5}{6}\)
=\(\frac{1}{4}\)+\(\frac{5}{6}\)
=\(\frac{6}{24}\)+\(\frac{20}{24}\)
=\(\frac{13}{12}\)