Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
1,
a,-3/5
b,-1/2
c,19/39
d,1/4
e,-39/40
f,-59/56
2,
a,=
b,<
c,>
d,<
k cho mình nha
A,-3/-7+5/19+-4/7
=(-3/-7+-4/7)+5/19
=-1/7+5/19=16/133
B,-13/24+-5/24+7/21
=-3/4+7/21=-5/12
C,-5/13+(-8/13+1)
=(-5/13+-8/13)+1
=-1+1=0
D,2/3+(3/8+-2/3)
=(2/3+-2/3)+3/8
=0+3/8=3/8
E,(-3/4+5/8)+-1/8
=-1/8+1/8=0
a; \(\dfrac{9}{4}\) - \(\dfrac{-11}{4}\)
= \(\dfrac{9}{4}\) + \(\dfrac{11}{4}\)
= \(\dfrac{20}{4}\)
= 5
b; \(\dfrac{7}{8}\) - \(\dfrac{3}{-8}\) - \(\dfrac{1}{8}\)
= \(\dfrac{7}{8}\) + \(\dfrac{3}{8}\) - \(\dfrac{1}{8}\)
= \(\dfrac{7+3-1}{8}\)
= \(\dfrac{9}{8}\)
c; \(\dfrac{-5}{21}\) - \(\dfrac{25}{21}\) - \(\dfrac{-1}{21}\)
= \(\dfrac{-5}{21}\) - \(\dfrac{25}{21}\) + \(\dfrac{1}{21}\)
= \(\dfrac{-5-25+1}{21}\)
= \(\dfrac{-29}{21}\)
a: =35/17-18/17-9/5+4/5
=1-1=0
b: =-7/19(3/17+8/11-1)
=7/19*18/187=126/3553
c: =26/15-11/15-17/3-6/13
=1-6/13-17/3
=7/13-17/3=-200/39
a) 1+(-3)+5+(-7)+9+(-11)+13+(-15)
= [1+(-3)]+[5+(-7)]+[9+(-11)]+[13+(-15)]
=(-2)+(-2)+(-2)+(-2)
=(-2).4
=-8
b) (-1)+3+(-5)+7+...+(-2005)+2007
=[(-1)+3]+[(-5)+7]+...+[(-2005)+2007]
=2+2+...+2
Từ 1 đến 2007 có : (2007-1)/2+1=1004 số
Mà cứ 2 số ta được 1 cặp
=>1004/2=502 cặp
=>2.502=1004
Câu c) làm tương tự câu b) nha
Nhớ **** cho mình nha ^-^
\(\left(19\frac{5}{8}:\frac{7}{12}-13\frac{1}{4}:\frac{7}{12}\right).\frac{4}{5}\)
\(=\left(\frac{157}{8}:\frac{7}{12}-\frac{53}{4}:\frac{7}{12}\right).\frac{4}{5}\)
\(=\left[\left(\frac{157}{8}-\frac{53}{4}\right):\frac{7}{12}\right].\frac{4}{5}\)
\(=\left[\frac{51}{8}:\frac{7}{12}\right].\frac{4}{5}\)
\(=\frac{153}{14}.\frac{4}{5}\)
\(=\frac{306}{35}\)
\(\left(\frac{-2}{5}+\frac{3}{7}\right)-\left(\frac{4}{9}+\frac{12}{20}-\frac{13}{35}\right)+\frac{7}{35}\)
\(=\frac{1}{35}-\frac{212}{315}+\frac{7}{35}\)
\(=\frac{1}{35}+\frac{-212}{315}+\frac{7}{35}\)
\(=\frac{9}{315}+\frac{-212}{315}+\frac{63}{315}\)
\(=\frac{-140}{315}=\frac{-4}{9}\)
1+2-3-4+5+6-7-8+9+................+33
=1+(2-3-4+5)+(6-7-8+9)+............+(30-31-32+33)
=1+0+0+..............+0
=1
\(a,\frac{6}{-25}+\frac{-9}{25}=\frac{-3}{5}\)
\(b,\frac{1}{8}+\frac{-5}{8}=\frac{-1}{2}\)
\(c,\frac{11}{13}+\frac{-14}{39}=\frac{19}{39}\)
\(d,\frac{7}{14}+\frac{9}{-36}=\frac{1}{4}\)