\(\frac{4}{17}-\frac{7}{15}+\frac{13}{17}-\frac{8}{15}+\frac{5}{8}-\frac{7}{16}\)
Các bn xem đề có sai hum nhé! :)))
Ko sai thì giải nhé :))
Tính nhanh:
\(\frac{4}{17}-\frac{7}{15}+\frac{13}{17}-\frac{8}{15}+\frac{5}{8}-\frac{7}{16}\)
\(=\left(\frac{4}{17}+\frac{13}{17}\right)-\left(\frac{7}{15}+\frac{8}{15}\right)+\left(\frac{10}{16}-\frac{7}{16}\right)\)
\(=1-1+\frac{3}{16}\)
\(\frac{3}{16}\)
gộp 1,3
2,4
5,6
thì ra 17/17-15/15+3/16=3/16
hk tốt!
\(\frac{5}{17}+\frac{-9}{15}+\frac{-2}{17}+\frac{-2}{5}\)
nếu có sai thì chắc sai ở chỗ \(\frac{-2}{5}\)thành \(\frac{-2}{15}\)ý mà nhưng chắc ko phải đâu các bn giúp m trong tối nay nha lm ơn
( 5/17+-2/17)+(-9/15+-2/5)
=(5/17+-2/17)+(-9/15+-6/15)
=3/17+-15/15
=3/17+(-1)
=(-14)/17
k mình nha! căm ơn bạn!!!!
= (5/17-2/17) - (9/15+2/5)
= 3/17 - 1
= -14/17
Tk mk nha
\(\frac{5}{17}+\frac{-9}{15}+\frac{-2}{17}+\frac{-2}{5}\)
\(=\frac{5}{17}+\frac{-9}{15}+\frac{-2}{17}+\frac{-6}{15}\)
\(=\left(\frac{5}{17}+\frac{-2}{17}\right)+\left(\frac{-9}{15}+\frac{-6}{15}\right)\)
\(=\frac{3}{17}+\frac{-15}{15}\)
\(=\frac{3}{17}+\left(-1\right)\)
\(=\frac{-14}{17}\)
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
Tính
a) A= \(\frac{1}{3}-\frac{3}{5}+\frac{5}{7}-\frac{7}{9}+\frac{9}{11}-\frac{11}{13}-\frac{9}{11}+\frac{7}{9}-\frac{5}{7}+\frac{3}{5}-\frac{1}{3}\)
b) B= \(\frac{3}{2}+\frac{5}{4}+\frac{9}{8}+\frac{17}{16}+\frac{33}{32}+\frac{65}{64}-7\)
Các bạn trình bày cách làm nhé ( nếu các bạn ko trình bày cách làm thì ko đc like đâu ạ!!!!!!!!!)
A=\(\frac{1}{3}-\frac{3}{5}+\frac{5}{7}-\frac{7}{9}+\frac{9}{11}-\frac{11}{13}-\frac{9}{11}+\frac{7}{9}-\frac{5}{7}+\frac{3}{5}-\frac{1}{3}\)
A=[ \(\frac{1}{3}-\frac{1}{3}\)] + [ \(-\frac{3}{5}+\frac{3}{5}\)] + [ \(-\frac{5}{7}+\frac{5}{7}\)] + [ \(-\frac{7}{9}+\frac{7}{9}\)] + [ \(-\frac{9}{11}+\frac{9}{11}\)] \(-\frac{11}{13}\)
Các bạn tự làm tiếp nhé!Sorry
sắp xếp các phân số sau theo thứ tự từ bé đến lớn :
a ) \(\frac{7}{10}\ ,\ \frac{10}{13}\ ,\ \)\(\frac{4}{7}\ ,\ \frac{1}{4}\ ,\ \frac{13}{16}\ ,\ \frac{16}{19}\ .\)
b ) \(\frac{13}{10}\ ,\ \frac{17}{14}\ ,\ \frac{11}{8}\ ,\ \frac{8}{5}\ ,\ \frac{18}{15}\ ,\ \frac{21}{18}\)
a,\(\frac{-5}{9}+\frac{8}{15}+\frac{-2}{11}+\frac{4}{-9}+\frac{7}{15}\)
b,\(\frac{5}{13}+\frac{-5}{17}+\frac{-20}{41}+\frac{8}{13}+\frac{-21}{41}\)
c,\(\frac{1}{5}+\frac{-2}{9}+\frac{-7}{9}+\frac{4}{5}+\frac{16}{17}\)
d,\(\frac{2}{3.5}+\frac{2}{5.7}+\frac{2}{7.9}+......+\frac{2}{99.101}\)
a,\(=\frac{-5}{9}+\frac{8}{15}+\frac{-2}{11}+\frac{-4}{9}+\frac{7}{15}\)
\(\left(\frac{-5}{9}+\frac{-4}{9}\right)+\left(\frac{8}{15}+\frac{7}{15}\right)+\frac{-2}{11}\)
=-1+1+-2/11
=0+-2/11
=-2/11
b,\(=\left(\frac{5}{13}+\frac{8}{13}\right)+\left(\frac{-20}{41}+\frac{-21}{40}\right)+\frac{-5}{17}\)
=1+-1+-5/17
=0+-5/17
=-5/17
c,\(=\left(\frac{1}{5}+\frac{4}{5}\right)+\left(\frac{-2}{9}+-\frac{7}{9}\right)+\frac{16}{17}\)
=1+-1+16/17
=0+16/17
=16/17
d,\(=\frac{1}{3}-\frac{1}{5}+\frac{1}{5}-\frac{1}{7}+\frac{1}{7}-\frac{1}{9}+...+\frac{1}{99}-\frac{1}{101}\)
\(=\frac{1}{3}-\frac{1}{101}=\frac{98}{303}\)
a.\(\frac{-5}{9}\)+\(\frac{8}{15}\)+\(\frac{-2}{11}\)+\(\frac{4}{-9}\)+\(\frac{7}{15}\)
=\(\frac{-5}{9}\)+\(\frac{4}{-9}\)+\(\frac{8}{15}\)+\(\frac{7}{15}\)+\(\frac{-2}{11}\)
=(\(\frac{-5}{9}\)+\(\frac{-4}{9}\))+(\(\frac{8}{15}\)+\(\frac{7}{15}\))+\(\frac{-2}{11}\)
=(-1)+1+\(\frac{-2}{11}\)
=0+\(\frac{-2}{11}\)
=\(\frac{-2}{11}\).
Bài 12 : Thực hiện phép tính một cách hợp lí:
p) \(\frac{-5}{9}+\frac{8}{15}+\frac{-2}{11}+\frac{4}{-9}+\frac{7}{15}\) q) \(\frac{5}{13}+\frac{-5}{17}+\frac{-20}{41}+\frac{8}{13}+\frac{-21}{41}\) r) \(\frac{1}{5}+\frac{-2}{9}+\frac{-7}{9}+\frac{4}{5}+\frac{16}{17}\)
p) \(\frac{-5}{9}+\frac{8}{15}+\frac{-2}{11}+\frac{4}{-9}+\frac{7}{15}\)
\(=\left(\frac{-5}{9}+\frac{-4}{9}\right)+\left(\frac{8}{15}+\frac{7}{15}\right)+\frac{-2}{11}\)
\(=-1+1+\frac{-2}{11}\)
\(=-\frac{2}{11}\)
q) \(\frac{5}{13}+\frac{-5}{17}+\frac{-20}{41}+\frac{8}{13}+\frac{-21}{41}\)
\(=\left(\frac{5}{13}+\frac{8}{13}\right)+\left(\frac{-20}{41}+\frac{-21}{41}\right)+\frac{-5}{17}\)
\(=1+\left(-1\right)+\frac{-5}{17}=\frac{-5}{17}\)
r) \(\frac{1}{5}+\frac{-2}{9}+\frac{-7}{9}+\frac{4}{5}+\frac{16}{17}\)
\(=\left(\frac{1}{5}+\frac{4}{5}\right)+\left(\frac{-2}{9}+\frac{-7}{9}\right)+\frac{16}{17}\)
\(=1+\left(-1\right)+\frac{16}{17}=\frac{16}{17}\)
a) \(3\frac{14}{19}+\frac{13}{17}+\frac{35}{43}+6\)
b) \(\frac{\frac{15}{12}+\frac{3}{4}-1}{3-\frac{5}{6}+\frac{2}{3}}+\frac{\frac{16}{5}+\frac{16}{7}-\frac{16}{9}}{\frac{17}{5}+\frac{17}{7}-\frac{17}{9}}\)
\(3\frac{14}{19}+\frac{13}{17}+\frac{35}{43}+6\)
\(=\frac{71}{19}+\frac{13}{17}+\frac{35}{43}+6\)
\(=\frac{1454}{323}+\frac{35}{43}+6\)
\(=5,...+6\)
\(=11,...\)
\(Bai2a\)\(A=\frac{\sqrt{3}-\sqrt{6}}{1-\sqrt{2}}-\frac{2+\sqrt{8}}{1+\sqrt{2}}\)
\(=\frac{\sqrt{3}\left(1-\sqrt{2}\right)}{1-\sqrt{2}}-\frac{2\left(1+\sqrt{2}\right)}{1+\sqrt{2}}\)
\(=\sqrt{3}-2\)
\(VayA=\sqrt{3}-2\)
Giúp tôi bài này với ai giải hết được cho đúng luôn:) \(7-\frac{12}{13};7\frac{2}{5}-3\frac{2}{9};4\frac{2}{5}-2\frac{6}{7};17\frac{2}{31}-\left(\frac{15}{17}+6\frac{2}{31}\right)\).Nhớ làm rõ ra nhé nếu không sẽ không được tính