rút gọn các phân số sau:
(-5)3.40.4\135.(-2)14.(-100)0
2929-101\2.1919-404
2.3+4.6+14.21\3.5+6.10+21.36
18.34+(-18).124\-36.17+9.(-52)
rút gọn phân số:
1, -1997.1996+1 / (-1995).(-1997)+1996
2, 2.3+4.6+14.21 / 3.5+6.10+21.35
3, 3.7.13.37.39-10101 / 505050 - 70707
4, 18.34+(-18).124 / -36.17+9.(-52)
Rút gọn phân số:
a)\(\frac{2929-101}{2.1919+404}\)
b)\(\frac{-1997.1996+1}{-1995.\left(-1997\right)+1996}\)
c)\(\frac{2.3+4.6+14.21}{3.5+6.10+21.35}\)
d)\(\frac{3.7.13.37.39-10101}{505050-70707}\)
e)\(\frac{18.34+\left(-18\right).124}{-36.17+9.\left(-52\right)}\)
dễ quá đi. Nếu muốn mình giải hãy k trước đi
a) \(\frac{2929-101}{2.1919+404}\)\(=\frac{101.29-101}{2.1919+2.202}\)\(=\frac{101\left(29-1\right)}{2\left(1919+202\right)}\)\(=\frac{101.28}{2.2121}\)\(=\frac{2.101.7.2}{2.101.7.3}\)\(=\frac{2}{3}\)
b) \(\frac{-1997.1996+1}{-1995\left(-1997\right)+1996}\)\(=\frac{-1997.\left(1995+1\right)+1}{-1995\left(-1997\right)+1996}\)\(=\frac{-1997.1995-1997+1}{-1\left(-1997\right).1995+1996}\)\(=\frac{-1997.1995-1996}{1997.1995+1996}\)\(=\frac{-\left(1997.1995+1996\right)}{1997.1995+1996}\)\(=-1\)
c) \(\frac{2.3+4.6+14.21}{3.5+6.10+21.35}\)\(=\frac{2.3+4.2.3+2.7.3.7}{3.5+2.3.2.5+3.7.5.7}\)\(=\frac{2.3\left(1+4+7.7\right)}{3.5\left(1+2.2+7.7\right)}\)\(=\frac{2\left(1+4+49\right)}{5\left(1+4+49\right)}\)\(=\frac{2}{5}\)
d) \(\frac{3.7.13.37.39-10101}{505050-70707}\)\(=\frac{3.7.13.37.39-3.7.13.37}{2.3.5.5.7.13.37-3.7.7.13.37}\)\(=\frac{3.7.13.37\left(39-1\right)}{3.7.13.37\left(2.5.5-7\right)}\)\(=\frac{38}{43}\)
e) \(\frac{18.34+\left(-18\right).124}{-36.17+9.\left(-52\right)}\)\(=\frac{18.2.17-18.2.62}{\left(-1\right).2.2.3.3.17+\left(-1\right)2.2.3.3.13}\)\(=\frac{18.2\left(17-62\right)}{\left(-1\right).2.2.3.3\left(17+13\right)}\)\(=\frac{\left(-1\right).2.2.3.3.45}{\left(-1\right).2.2.3.3.30}\)\(=\frac{45}{30}\)\(=\frac{3}{2}\)
a, \(\frac{29.101-101}{2.101.19+4.101}=\frac{101.\left(29-1\right)}{38.101+4.101}=\frac{101.28}{101.42}=\frac{28}{42}=\)\(\frac{2}{3}\)
b, \(\frac{-1997.1996+1}{-1995.\left(-1997\right)+1996}=\frac{-1997.\left(1995+1\right)+1}{1995.1997+1996}\)\(=\frac{-1997.1995+1997-1}{1995.1997+1996}=\frac{-1997.1995+1996}{1995.1997+1996}=-1\)
c,\(\frac{2.3+2\left(2.3\right)+7\left(2.3\right)}{3.5+2\left(3.5\right)+7\left(3.5\right)}=\frac{2.3\left(1+2+7\right)}{3.5\left(1+2+7\right)}=\frac{2.3}{3.5}=\frac{2}{5}\)
d,\(\frac{3.7.13.37.39-3.7.13.37}{2.3.5^2.7.13.37-3.7^2.13.37}=\frac{3.7.13.37.38}{3.7.13.37\left(2.5^2-7\right)}\)\(=\frac{3.7.13.37.38}{3.7.13.37.43}=\frac{38}{43}\)
e, \(\frac{18.34+18.\left(-124\right)}{9.\left(-4\right).17+9.\left(-52\right)}=\frac{18\left(-124+34\right)}{9.\left(-68\right)+9\left(-52\right)}\)\(=\frac{18\left(-90\right)}{9\left(-120\right)}=\frac{18.\left(-90\right)}{9.2\left(-60\right)}=\frac{18.\left(-90\right)}{18.\left(-60\right)}=\)\(\frac{-90}{-60}=\frac{3}{2}\)
Rút gọn phân số
\(\frac{2.3+4.6+14.21}{3.5+6.10+21.35}\) ; \(\frac{3.7.13.37.39-10101}{505050-70707}\) ; \(\frac{18.34+\left(-18\right).124}{-36.17+9.\left(-52\right)}\)
a)\(\frac{-135}{540}\)
b)\(\frac{25.13}{26.35}\)
c)\(\frac{6.9-2.17}{63.3-119}\)
d)\(\frac{3.13-13.18}{15.40-80}\)
e)\(\frac{-5^3.40.4^4}{135.\left(-2\right)^{14}.\left(-100\right)^0}\)
f)\(\frac{2929-101}{2.1919+404}\)
g)\(\frac{-1997.1996+1}{\left(-1995\right).\left(-1997\right)+1996}\)
h)\(\frac{2.3+4.6+14.21}{3.5+6.10+21.35}\)
i)\(\frac{3.7.13.37.39-10101}{505050-70707}\)
k)\(\frac{18.34+\left(-18\right).124}{-36.17+9.\left(-52\right)}\)
1.Tính tổng: \(\frac{5}{1.3}+\frac{5}{3.5}+\frac{5}{5.7}+....+\frac{5}{99.101}\)
2.Rút gọn phân số:
a)\(\frac{2929-101}{2.1919+404}\) b)\(\frac{6.9-2.17}{63.3-119}\)
c)\(\frac{3.13-13.18}{15.40-80}\) d)\(\frac{\left(-5\right)^3.40.4^3}{135.\left(-2\right)^{14}.\left(-100\right)^0}\)
e)\(\frac{-1997.1996+1}{-1995.\left(-1997\right)+1996}\) f)\(\frac{2.3+4.6+14.21}{3.5+6.10+21.35}\)
f)\(\frac{2.3+4.6+14.21}{3.5+6.10+21.35}\) g)\(\frac{3.7.13.37.39-10101}{505050-70707}\)
h)\(\frac{18.34+\left(-18\right).124}{-36.17+9.\left(-52\right)}\)
Bài 1:
Coi \(A=\frac{5}{1.3}+\frac{5}{3.5}+\frac{5}{5.7}+....+\frac{5}{99.101}\)
\(2A=\left(\frac{5}{1.3}+\frac{5}{3.5}+\frac{5}{5.7}+....+\frac{5}{99.101}\right).2\)
\(=5.\left(\frac{2}{1.3}+\frac{2}{3.5}+\frac{2}{5.7}+....+\frac{2}{99.101}\right)\)
\(=5.\left(1-\frac{1}{3}+\frac{1}{3}-\frac{1}{5}+...+\frac{1}{99}-\frac{1}{101}\right)\)
\(=5.\left(1-\frac{1}{101}\right)\)
\(=5.\frac{100}{101}\)
\(=\frac{500}{101}\Rightarrow A=\frac{500}{101}:2=\frac{250}{101}\)
\(\left(\frac{5}{1}-\frac{5}{3}+\frac{5}{3}-\frac{5}{5}....+\frac{5}{99}-\frac{5}{101}\right):\frac{1}{5}\)
\(\left(\frac{1}{1}-\frac{1}{3}+\frac{1}{3}-\frac{1}{5}.....+\frac{1}{99}-\frac{1}{101}\right).5\)
\(\left(\frac{1}{1}-\frac{1}{101}\right).5\)
\(\frac{100}{101}.5\)
\(\frac{500}{101}\)
2,a,\(\frac{2929-101}{3838+404}\)\(=\frac{2828}{4242}=\frac{2}{3}\)
\(b,\frac{54-34}{189-119}=\frac{20}{70}=\frac{2}{7}\)
\(c,d,e,f,f,g,h\)\(tuong\) \(tu\)
\(\frac{5}{1.3}+\frac{5}{3.5}+\frac{5}{5.7}+...............+\frac{5}{99.101}\)
\(=\frac{5.2}{1.3.2}+\frac{5.2}{3.5.2}+\frac{5.2}{5.7.2}+............+\frac{5.2}{99.101.2}\)
\(=\frac{5}{2}.\left(\frac{2}{1.3}+\frac{2}{3.5}+.................+\frac{2}{99.101}\right)\)
\(=\frac{5}{2}.\left(\frac{1}{1}-\frac{1}{3}+\frac{1}{3}-\frac{1}{5}+.........+\frac{1}{99}-\frac{1}{101}\right)\)
\(=\frac{5}{2}.\left(1-\frac{1}{101}\right)\)
\(=\frac{5}{2}.\frac{100}{101}\)
\(=\frac{250}{101}\)
Rút gọn phân số
2.3+4.6+14.21/3.5+6.10+21.35
2.3+4.6+14.21/3.5+6.10+21.35
= 2 . 3 + 2 . 2 . 3 . 2 + 7 .
\(\frac{2\cdot3+4\cdot6+14\cdot21}{3\cdot5+6\cdot10+21\cdot35}\)=\(\frac{2\cdot3\cdot\left(1+2\cdot2+7\cdot7\right)}{3\cdot5\cdot\left(1+2\cdot2+7\cdot7\right)}\)
Sau đó ta chia tử và mẫu cho (1+2*2+7*7) thì ta có phân số
\(\frac{2\cdot3}{3\cdot5}\)=\(\frac{2}{5}\)(rút gọn tử và mẫu cho 3)
* Rút gọn :
a) \(\frac{\left(-5\right)^3.40.4^3}{135.\left(-2\right)^{14}.\left(-100\right)^0}\).
b) \(\frac{2929-101}{2.1919+404}\).
c) \(\frac{2.3+4.6+14.21}{3.5+6.10+21.35}\).
d) \(\frac{-1997.1996+1}{\left(-1995\right).\left(-1997\right)+1996}\).
e) \(\frac{3.7.13.37.39-10101}{505050-70707}\).
f) \(\frac{18.34+\left(-18\right).124}{-36.17+9.\left(-52\right)}\).
Thanks~~~~ Helps~~~~Please 3:)
*Ai nhanh và dúng mình sẽ tick cho !!!!
Tìm x:
LƯU Ý: VD: A VÀ A/B CÓ NGHĨA LÀ HỖN SỐ NHÉ !
a) 2/3x-1/2x= 5/12
b) 5 và 8/17: x+(-4/17):x+3 và 1/7:17 và 1/3=4/11
Bài 2: Rút gọn phan số
a) \(\frac{\left(-5\right)^3.40.4^3}{135.\left(-2\right)^{14}.\left(-100\right)^0}\)
h)\(\frac{2.3+4.6+14.21}{3.5+6.10+21.35}\)
k)\(\frac{18.34+\left(-18\right).124}{-36.17+9.\left(-52\right)}\)
Câu cuối: \(\frac{3.7.13.37.39-10101}{505050-70707}\)
Bạn nào giải hết thì mình sẽ tick cho câu trả lời đó và có thể người đó sẽ đc mình tick cho tất cả câu trả lời của bạn ấy( có thể thôi nhá, nếu mình thấy thì mình sẽ tick cho) Mơn những bạn đã giúp mình
Rút gọn phân số
1\(\frac{6.9-2.17}{63.3-119}\)
2) \(\frac{2929-101}{2.1919+404}\)
3) \(\frac{-1997.1996+1}{\left(-1995\right).\left(-1997\right)+1996}\)
4) \(\frac{2.3+4.6+14.21}{3.5+6.10+21.35}\)
5) \(\frac{3.7.13.37.39+10101}{505050-707070}\)