a.4/5-(-2/7)-7/10
b,2/3-/(-4/7)-(1/2+3/8)/
Tính:
a) 1/8 x 4/5 : 6/10
b) (2/3 - 1/4) x 6/5
c) 24/35 : (4/5 x 8/7)
d) 3 + 5/7 - 1/3
a: \(\dfrac{1}{8}\cdot\dfrac{4}{5}:\dfrac{3}{5}=\dfrac{1}{10}\cdot\dfrac{5}{3}=\dfrac{1}{2\cdot3}=\dfrac{1}{6}\)
b: \(=\dfrac{8-3}{12}\cdot\dfrac{6}{5}=\dfrac{6}{12}=\dfrac{1}{2}\)
c: \(=\dfrac{24}{35}:\dfrac{32}{35}=\dfrac{3}{4}\)
d: =63/21+15/21-7/21=71/21
a \(\dfrac{1}{8}\times\dfrac{4}{5}\times\dfrac{10}{6}=\dfrac{1}{6}\)
b \(\left(\dfrac{8}{12}-\dfrac{3}{12}\right)\times\dfrac{6}{5}=\dfrac{5}{12}\times\dfrac{6}{5}=\dfrac{1}{2}\)
c \(\dfrac{24}{35}:\dfrac{32}{35}=\dfrac{24}{35}\times\dfrac{35}{32}=\dfrac{3}{4}\)
d \(\dfrac{63}{21}+\dfrac{15}{21}-\dfrac{7}{21}=\dfrac{71}{21}\)
Cho biết kết quả câu lệnh sau: For i:=1 to 10 do if i mod 2=0 then write(i:4); *
a.1 2 3 4 5 6 7 8 9 10
b.2 4 6 8 10
c.1 3 5 7 9
d.4 8
Chọn câu trả lời đúng.
A. 4/10 > 6/10
B. 5/7 > 1
C. 3/2 < 1/2
D. 8/4 = 2
a, 6/7 + 3/10
b, 5/9 + 1/3
c, 5/8 - 2/5
d, 1/4 - 1/7
Giúp mik với, mik cần gấp
\(a,\dfrac{6}{7}+\dfrac{3}{10}=\dfrac{60}{70}+\dfrac{21}{70}=\dfrac{81}{70}\\ b,\dfrac{5}{9}+\dfrac{1}{3}=\dfrac{5}{9}+\dfrac{3}{9}=\dfrac{8}{9}\\ c,\dfrac{5}{8}-\dfrac{2}{5}=\dfrac{25}{40}-\dfrac{16}{40}=\dfrac{9}{40}\\ d,\dfrac{1}{4}-\dfrac{1}{7}=\dfrac{7}{28}-\dfrac{4}{28}=\dfrac{3}{28}\)
a)4/5-(-2/7)-7/10
b)3,5-(-2/7)
c) (-3)x(-7/12)
\(\dfrac{4}{5}-\left(-\dfrac{2}{7}\right)-\dfrac{7}{10}\\ =\dfrac{4}{5}+\dfrac{2}{7}-\dfrac{7}{10}\\ =\dfrac{56}{70}+\dfrac{20}{70}-\dfrac{49}{70}\\ =\dfrac{27}{70}\\ 3,5-\left(-\dfrac{2}{7}\right)\\ =\dfrac{7}{2}+\dfrac{2}{7}\\ =\dfrac{49}{14}+\dfrac{4}{14}\\ =\dfrac{53}{14}\\ \left(-3\right).\left(-\dfrac{7}{12}\right)\\ =\dfrac{21}{12}\\ =\dfrac{7}{4}\)
1.a 2 5 1 4 3 10b 8 12 3 7 9 7 c 1 6 x 4 9 5 9 x 1 6 1d 183 93 1 5 2 x 102 1 2 3 4 1 2021 2.a 3 5 x 0,8b 1 4 3 4 x 2 5c x 1 2 8 25 x 1 cái gạch ngang là gạch phân số ạ VD một phần hai 1 2mong mng giúp em sớm ạ
Xin lỗi m.n nhé gửi nhầm tí
1. Rút Gọn
a)√6-2√5
b)√8+2√7
2 Tính
a) √(√10-3)2 -√10
b)√(5+√7)2 - √8-2√7
\(1,\)
\(a,\sqrt{6-2\sqrt{5}}=\sqrt{\sqrt{5^2}-2.\sqrt{5}.1+1}=\sqrt{\left(\sqrt{5}-1\right)^2}=\left|\sqrt{5}-1\right|=\sqrt{5}-1\)
\(b,\sqrt{8+2\sqrt{7}}=\sqrt{\sqrt{7^2}+2.\sqrt{7}.1+1}=\sqrt{\left(\sqrt{7}+1\right)^2}=\left|\sqrt{7}+1\right|=\sqrt{7}+1\)
\(2,\)
\(a,\sqrt{\left(\sqrt{10}-3\right)^2}-\sqrt{10}\)
\(=\left|\sqrt{10}-3\right|-\sqrt{10}\)
\(=\sqrt{10}-\sqrt{10}-3\)
\(=-3\)
\(b,\sqrt{\left(5+\sqrt{7}\right)^2}-\sqrt{8-2\sqrt{7}}\)
\(=\left|5+\sqrt{7}\right|-\sqrt{\left(\sqrt{7}-1\right)^2}\)
\(=5+\sqrt{7}-\left|\sqrt{7}-1\right|\)
\(=5+\sqrt{7}-\sqrt{7}+1\)
\(=6\)
Trong ngôn ngữ Pascal, đoạn chương trình sau đưa ra kết quả gì?
For i := 1 to 10 do Write (i,' ');
A. 1 2 3 4 5 6 7 8 9 10
B. 10 9 8 7 6 5 4 3 2 1
C. Đưa ra 10 dấu cách
D. Không đưa ra kết quả gì