so sánh 2 phân số sau \(\frac{3}{-4}vs\frac{-1}{-4}\): \(\frac{15}{17}vs\frac{25}{27}\)
So sánh giùm mik nha.
a) \(\frac{3}{-4}v\text{à}\frac{-1}{-4}\)
b) \(\frac{15}{17}v\text{à}\frac{25}{27}\)
c) \(\frac{-9}{6}v\text{à}\frac{6}{-4}\)
d) \(\frac{2000}{2001}+\frac{2001}{2002}v\text{à}\frac{2000+2001}{2001+2002}\)
Lm đc bài nào thì giải giúp mik vs nha.
a) \(\frac{3}{-4}=\frac{-3}{4};\frac{-1}{-4}=\frac{1}{4}\)
Vì - 3 < 1 nên \(\frac{-3}{4}< \frac{1}{4}\)
hay \(\frac{3}{-4}< \frac{-1}{-4}\)
Quy đồng mẫu ta được:
15/17=15.27/17.27=405/459
25/27=25.17/27.27=425/459
⇒405/459<425/459⇒15/17<25/27
c) quy đồng
-9/6=-36/24
6/-4=36/-24
tương đương -36/24=-36/24
suy ra -9/6=6/-4
Tính giá trị biểu thức
\(1.A=\frac{1}{5}+\frac{3}{17}-\frac{4}{3}+\left(\frac{4}{5}-\frac{3}{17}+\frac{1}{3}\right)-\frac{1}{7}+\left[\frac{-14}{30}\right]\)
\(2.B=\left(\frac{5}{8}-\frac{4}{12}+\frac{3}{2}\right)-\left(\frac{5}{8}+\frac{9}{13}\right)-\left[\frac{-3}{2}\right]+\frac{7}{-15}\)
\(3.C=\frac{5}{18}+\frac{8}{19}-\frac{7}{21}+\left(\frac{-10}{36}+\frac{11}{19}+\frac{1}{3}\right)-\frac{5}{8}\)
\(4.D=\frac{1}{9}-\left[\frac{-5}{23}\right]-\left(\frac{-5}{23}+\frac{1}{9}+\frac{25}{7}\right)+\frac{50}{14}-\frac{7}{30}\)
\(5.E=\frac{1}{13}+\left(\frac{-5}{18}-\frac{1}{13}+\frac{12}{17}\right)+\left(\frac{12}{17}+\frac{5}{18}+\frac{7}{5}\right)\)
\(6.F=\frac{15}{14}-\left(\frac{17}{23}-\frac{80}{87}+\frac{5}{4}\right)+\left(\frac{12}{17}-\frac{15}{14}+\frac{1}{4}\right)\)
\(7.G=\frac{1}{25}-\frac{4}{27}+\left(\frac{-23}{27}+\frac{-1}{25}-\frac{5}{43}\right)+\frac{5}{43}-\frac{4}{7}\)
\(8.H=\frac{4}{15}-\frac{23}{28}-\left(\frac{-23}{28}+\frac{-11}{15}-\frac{29}{27}\right)-\frac{2}{27}\)
\(9.K=\frac{1}{16}-\frac{5}{21}+\left(\frac{-1}{16}+\frac{-3}{5}-\frac{-5}{21}\right)+\frac{-2}{5}+\frac{3}{4}\)
\(10.L=\frac{7}{12}+\frac{15}{14}-\left(\frac{14}{22}+\frac{-1}{14}+\frac{5}{21}\right)-\frac{-5}{21}+\frac{3}{5}\)
yutyugubhujyikiu
quy đồng mẫu các phân số sau:
\(a.\frac{3}{8}và\frac{5}{27};b.\frac{-2}{9}và\frac{4}{25};c.\frac{1}{15}và-6\)
So sánh
\(\frac{1}{3}+\frac{2}{3^2}+\frac{3}{3^3}+\frac{4}{3^4}+...+\frac{100}{3^{100}}vs\frac{3}{4}\)
So sánh 2 phân số sau:
\(\frac{2^{23}+1}{2^{25}+1}va\frac{2^{25}+1}{2^{27}+1}\)
Vì \(2^{25}+1< 2^{27}+1\) nên \(\frac{2^{25}+1}{2^{27}+1}< 1\)
\(\Rightarrow\frac{2^{25}+1}{2^{27}+1}< \frac{2^{25}+1+3}{2^{27}+1+3}=\frac{2^{25}+4}{2^{27}+4}=\frac{2^2\left(2^{23}+1\right)}{2^2\left(2^{25}+1\right)}=\frac{2^{23}+1}{2^{25}+1}\)
Vậy \(\frac{2^{25}+1}{2^{27}+1}< \frac{2^{23}+1}{2^{25}+1}\)
1/Tính họp lí(nếu có thể):
a, \(5-\frac{1}{3}-1\frac{2}{3}+\frac{1}{2}\)\
b,\(\frac{3}{2}.\frac{4}{9}-\frac{1}{5}-\frac{2}{15}\)
c,\(\frac{25^{21}.7^{30}}{5^{40}.49^{15}.10}\)
d,\(\frac{3^{18}.25^5}{15^{10}.27^3}\)
Giup vs mk pải nộp gấp
\(\frac{\frac{4}{17}-\frac{4}{45}+\frac{1}{39}}{\frac{3}{17}-\frac{1}{15}+\frac{1}{52}}\)
Giúp mik vs ai nhanh mik tick cho ^-^
\(\frac{\frac{4}{17}-\frac{4}{45}+\frac{4}{156}}{\frac{3}{17}-\frac{3}{45}+\frac{3}{156}}=\frac{4.\left(\frac{1}{17}-\frac{1}{45}+\frac{1}{156}\right)}{3.\left(\frac{1}{17}-\frac{1}{45}+\frac{1}{156}\right)}=\frac{4}{3}\)
\(\frac{\frac{4}{17}-\frac{4}{45}+\frac{1}{39}}{\frac{3}{17}-\frac{1}{15}+\frac{1}{52}}\)
\(=\frac{\frac{4}{17}-\frac{4}{45}+\frac{4}{156}}{\frac{3}{17}-\frac{3}{45}+\frac{3}{156}}\)
\(=\frac{\frac{1}{17}.4-\frac{1}{45}.4+\frac{1}{156}.4}{\frac{1}{17}.3-\frac{1}{45}.3+\frac{1}{156}.3}\)
\(=\frac{4\left(\frac{1}{17}-\frac{1}{45}+\frac{1}{156}\right)}{3\left(\frac{1}{17}-\frac{1}{45}+\frac{1}{156}\right)}\)
\(=\frac{4}{3}\)
so sánh
\(\frac{15}{17}và\frac{25}{27}\)
Vì 15.27 < 17.25 nên \(\frac{15}{17}< \frac{25}{27}\)
Ta có:
15/17=405/459
25/27=425/459
Vậy 15/17>25/27
So sánh phân số
a/ \(\frac{33}{38}va\frac{61}{66}\)
b/ \(\frac{17}{30}va\frac{51}{92}\)
c/ \(\frac{22}{67}va\frac{51}{152}\)
d/ \(\frac{-45}{47}va\frac{31}{-30}\)
giúp mk vs nha, gồm có
1. Quy đồng \
2. Nhân chéo
3. Tính bắc cầu
4. So sánh bù
trong máy cái đó phải có 4 yếu tố đó nha
d.
\(-\frac{31}{30}< -1\)
\(-1< -\frac{45}{47}\)
\(\Rightarrow-\frac{31}{30}< -\frac{45}{47}\)
Chúc bạn học tốt
trong 4 yếu tố trên mà bn
vs lại giúp mk mấy câu kia lun
Thật sự mik ko hỉu đề bài mấy, bn ns rõ hơn đc ko?