tính nhanh
((\(\frac{5}{-7}+\frac{-5}{-7}+\frac{4}{3}\)
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Đặt P = ... ( biểu thức đề bài )
Nhận xét: Với \(k\inℕ^∗\) ta có:
\(\frac{k+2}{k!+\left(k+1\right)!+\left(k+2\right)!}=\frac{k+2}{k!+\left(k+1\right).k!+\left(k+2\right).k!}=\frac{k+2}{2.k!\left(k+2\right)}=\frac{1}{2.k!}\)
\(\Rightarrow\)\(P=\frac{1}{2.1!}+\frac{1}{2.2!}+...+\frac{1}{2.6!}=\frac{1}{2}\left(1+\frac{1}{2}+...+\frac{1}{720}\right)=...\)
A=\(\frac{\frac{3}{7}-\frac{3}{17}+\frac{3}{37}}{\frac{5}{7}-\frac{5}{17}+\frac{5}{37}}+\frac{\frac{1}{2}-\frac{1}{3}+\frac{1}{4}-\frac{1}{5}}{\frac{7}{5}-\frac{7}{4}+\frac{7}{3}-\frac{7}{2}}\)
\(=\frac{3\left(\frac{1}{7}-\frac{1}{17}+\frac{1}{37}\right)}{5\left(\frac{1}{7}-\frac{1}{17}+\frac{1}{37}\right)}+\frac{\frac{1}{2}-\frac{1}{3}+\frac{1}{4}-\frac{1}{5}}{-7\left(\frac{1}{2}-\frac{1}{3}+\frac{1}{4}-\frac{1}{5}\right)}\)
\(=\frac{3}{5}+\frac{1}{-7}=\frac{3}{5}-\frac{1}{7}\)
\(=\frac{21}{35}-\frac{5}{35}=\frac{16}{35}\)
\(\frac{\frac{3}{5}+\frac{3}{7}+\frac{3}{11}}{\frac{4}{5}+\frac{4}{7}+\frac{4}{11}}\)=3.\(\frac{3\left(\frac{1}{5}+\frac{1}{7}-\frac{1}{11}\right)}{4\left(\frac{1}{5}+\frac{1}{7}-\frac{1}{11}\right)}\)=\(\frac{3}{4}\)
\(M=\frac{\frac{3}{5}+\frac{3}{7}-\frac{3}{11}}{\frac{4}{5}+\frac{4}{7}-\frac{4}{11}}\)
\(M=\frac{3.\left(\frac{1}{5}+\frac{1}{7}-\frac{1}{11}\right)}{4.\left(\frac{1}{5}+\frac{1}{7}-\frac{1}{11}\right)}\)
\(M=\frac{3}{4}\)
bằng 3/4 nhé bạn mk thề đúng luôn
♨❤♨ -`ღ´- ⚕ ☤ ⚚ ྅ ࿓ ࿔ ༂ ༃ ༗ ༄ ༅ ༆ ༉ ༊ ࿐ ๛ ෴ ❤ ❥ ♛ ♚ 🍾 ☮ ✌ ☏ ☢ ☠ ✔ ☑ ♥ ❣ ♂ ♀ ⚤ Ⓐ ✍ ✉ ☣ ☤ ✘ ☒ ♡ ღ ツ ☼ ☁ ❅ ♒ ✎ © ® ™ Σ ℃ ℉ ° ✿ ϟ ☃ ☂ ✄ ¢ € £ ∞ ⌛ ¡ ⚑ ✞ ✡ ☪ ⌚ ¿ ☯ ➳ ⌘ ✈ ★ ½ ✯ ☭ ▼ ♫ ▲ ♪ ✪ ✫ 웃 유 ℂ ℍ ℕ ℙ ℚ ℝ ℤ ℬ ℰ ℯ ℱ ℊ ℋ ℎ ℐ ℒ ℓ ℳ ℴ ℘ ℛ ℭ ℮ ℌ ℑ ℜ ℨ α ß Á á À à Å å Ä ä Æ æ Ç ç É é È è Ê ê Í í Ì ì Î î Ñ ñ Ó ó Ò ò Ô ô Ö ö Ø ø Ú ú Ù ù Ü ü Ž ž ₳ ฿ ¢ € ₡ ¢ ₢ ₵ ₫ £ £ ₤ ₣ ƒ ₲ ₭ ₥ ₦ ₱ $ $ ₮ ₩ ₩ ¥ ¥ ₴ ₰ ¤ ៛ ₪ ₯ ₠ ₧ ₨ ᶀ ᶁ ᶂ ᶃ ᶄ ᶆ ᶇ ᶈ ᶉ ᶊ ᶋ ᶌ ᶍ ᶎ ᶏ ᶐ ᶑ ᶒ ᶓ ᶔ ᶕ ᶖ ᶗ ᶘ ᶙ ᶚ ᶸ ᵯ ᵰ ᵴ ᵶ ᵹ ᵼ ᵽ ᵾ ᵿ
()==[:::::::::::::>
▬▬ι═══════ﺤ
-═══════ι▬▬
┣▇▇▇═─
●▬▬▬▬๑۩۩๑▬▬▬▬▬●
█▬█ █ ▀█▀
█▄▄ ███ █▄▄
▄█▀ █▄ █▄█ ▀█▀
█▀█ █▄█ ▀█▀
█▄█▄█ █▄█ ▀█▀
cho mk 1 t.i.c.k
ta có: A = \(1\frac{4}{5}+2\frac{5}{7}+3\frac{4}{5}+4\frac{5}{7}\)
=\(1+\frac{4}{5}+2+\frac{5}{7}+3+\frac{4}{5}+4+\frac{5}{7}\)
=\(\left(1+2+3+4\right)+\left(\frac{4}{5}+\frac{4}{5}+\frac{5}{7}+\frac{5}{7}\right)\)
= 10 + \(\frac{106}{35}\)
= 10 + \(3\frac{1}{35}\)
= \(13\frac{1}{35}\)
\(\frac{5-\frac{5}{7}-\frac{5}{49}}{4-\frac{4}{7}-\frac{4}{49}}+\frac{1,5+75\%-\frac{3}{8}}{0.625-\frac{5}{2}-125\%}\)
\(=\frac{5.\left(\frac{1}{5}-\frac{1}{7}-\frac{1}{49}\right)}{4\cdot\left(\frac{1}{4}-\frac{1}{7}-\frac{1}{49}\right)}+\frac{\frac{3}{2}+\frac{3}{4}-\frac{3}{8}}{\frac{5}{8}-\frac{5}{2}-\frac{5}{4}}\)
\(=\frac{5}{4}+\frac{3\cdot\left(\frac{1}{2}+\frac{1}{4}-\frac{1}{8}\right)}{5\cdot\left(\frac{1}{8}-\frac{1}{2}-\frac{1}{4}\right)}\)
\(=\frac{5}{4}+\left(-\frac{3}{5}\right)\)
\(=\frac{13}{20}\)
\(\frac{\frac{3}{5}+\frac{3}{7}-\frac{3}{11}}{\frac{4}{5}+\frac{4}{7}-\frac{4}{11}}=\frac{3 \left(\frac{1}{5}+\frac{1}{7}-\frac{1}{11}\right)}{4\left(\frac{1}{5}+\frac{1}{7}-\frac{1}{11}\right)}=\frac{3}{4}\)
=3[1/5+1/7-1/11]
----------------------- =3/4
4[1/5+1/7-1/11]
Ta có:
G=\(3\frac{5}{7}+4\frac{3}{5}+1\frac{2}{7}\)\(+3\frac{1}{5}-\frac{4}{5}\)
=\(3+\frac{5}{7}+4+\frac{3}{5}+1+\frac{2}{7}+3+\frac{1}{5}-\frac{4}{5}\)
=\(\left(3+4+1+3\right)+\left(\frac{5}{7}+\frac{3}{5}+\frac{2}{7}+\frac{1}{5}-\frac{4}{5}\right)\)
=\(11+\left[\left(\frac{5}{7}+\frac{2}{7}\right)+\left(\frac{3}{5}+\frac{1}{5}-\frac{4}{5}\right)\right]\)
=\(11+\left[\frac{7}{7}+\frac{0}{5}\right]\)
=\(11+\left[1+0\right]\)
=\(11+1\)
=12
ĐÃ GIẢI CHI TIẾT RÙI NHÉ. **** NHA
\(\frac{5}{-7}+\frac{-5}{-7}+\frac{4}{3}\)
\(=\frac{-5}{7}+\frac{5}{7}+\frac{4}{3}\)
\(=0+\frac{4}{3}=\frac{4}{3}\)
Ủng hộ mk nha ^_-
5/-7+-5/-7+4/3
= -7/5+5/7/4/3
=-15/21+15/21+28/21
=28/21
=4/3