Tính: 3 7 : 5 11 = . . .
tính nhanh: 1/3-3/5+5/7-7/9+9/11-11/13+13/15+11/13-9/11+7/9-5/7+3/5-1/3
tính A=1/3-3/5+5/7-7/9+9/11-11/13-9/11+7/9-5/7+3/5-1/3
các bạn cho mình xin lời giải cụ thể với ạ
A=1/3-1/3-(3/5-3/5)+(5/7-5/7)-(7/9-7/9)+(9/11-9/11)-11/13
A=0-0+0-0+0-11/13
A=-11/13
tính
1/3-3/5+5/7-7/9+9/11-11/13+13/15+11/13-9/11+7/9-5/7+3/5
tính
1/3-3/5+5/7-7/9+9/11-11/13+13/15+11/13-9/11+7/9-5/7+3/5
\(\frac{1}{3}-\frac{3}{5}+\frac{5}{7}-\frac{7}{9}+\frac{9}{11}-\frac{11}{13}+\frac{13}{15}+\frac{11}{13}-\frac{9}{11}+\frac{7}{9}-\frac{5}{7}+\frac{3}{5}\)
\(=\left(-\frac{3}{5}+\frac{3}{5}\right)+\left(\frac{5}{7}-\frac{5}{7}\right)+\left(-\frac{7}{9}+\frac{7}{9}\right)+\left(\frac{9}{11}-\frac{9}{11}\right)+\left(-\frac{11}{13}+\frac{11}{13}\right)+\left(\frac{1}{3}+\frac{13}{15}\right)\)
\(=\frac{1}{3}+\frac{13}{15}\)
\(=\frac{6}{5}\)
Tính
1/3 - 3/5 + 5/7 - 7/9 + 9/11 - 11/13 - 9/11 + 7/9 - 5/7 + 3/5 - 1/3
\(\frac{1}{3}-\frac{3}{5}+\frac{5}{7}-\frac{7}{9}+\frac{9}{11}-\frac{11}{13}-\frac{9}{11}+\frac{7}{9}-\frac{5}{7}+\frac{3}{5}-\frac{1}{3}\)
\(=\left(\frac{1}{3}-\frac{1}{3}\right)+\left(\frac{3}{5}-\frac{3}{5}\right)+\left(\frac{5}{7}-\frac{5}{7}\right)+\left(\frac{7}{9}-\frac{7}{9}\right)+\left(\frac{9}{11}-\frac{9}{11}\right)-\frac{11}{13}\)
\(=0+0+0+0+0-\frac{11}{13}=-\frac{11}{13}\)
\(\frac{1}{3}-\frac{3}{5}+\frac{5}{7}-\frac{7}{9}+\frac{9}{11}+\frac{7}{9}-\frac{5}{7}+\frac{3}{5}-\frac{1}{3}\)
\(=\left(\frac{1}{3}-\frac{1}{3}\right)+\left(\frac{3}{5}-\frac{3}{5}\right)+\left(\frac{5}{7}-\frac{5}{7}\right)+\left(\frac{7}{9}-\frac{7}{9}\right)-\frac{11}{13}\)
\(=0+0+0+0+0-\frac{11}{13}=-\frac{11}{13}\)
XL mik thiếu 9/11 nha. Bài bạn dcv new lm đúng r
thực hiện phép tính(tính nhanh nếu có thể):
a)2/13 x 5/9+3/13 x 9/11+11/13
b)5/7 x -3/11+-5/7 x 8/11+9/7
Thực hiện phép tính
Thực hiện phép tính 1) 5 + (-4) 2) (-8) + 2 3) 8 + (-2) 4) 11 + (-3) 5) (-11) + 2 6) (-7) + 3 7) (-5) + 5 8) 11 + (-12) 9) (-18) + 20 10) (15) + (-12) 11) (-17) + 17 12) 16 + (-2) 13) (30) + (-14) 14) (-19) + 20 15) (-18) + 15 16) (10) + (-6) 17) (-28) + 14 18) 15+ (-30)19) (15) + (-4) 20) (-21) + 11 21) 8 + (-22) 22) (-15) + 4 23) (-3) + 2 24) 17 + (-14) 24) 17 + (-14)1) 5 + (-4) = 1
2) (-8) + 2 = -6
3) 8 + (-2) = 6
4) 11 + (-3) = 8
5) (-11) + 2 = -9
6) (-7) + 3 = -4
7) (-5) + 5 = 0
8) 11 + (-12) = -1
9) (-18) + 20 = 2
10) (15) + (-12) = 3
11) (-17) + 17 = 0
12) 16 + (-2) = 14
13) (30) + (-14) = 16
14) (-19) + 20 = 1
15) (-18) + 15 = -3
16) (10) + (-6) = 4
17) (-28) + 14 = -14
18) 15 + (-30) = -15
19) (15) + (-4) = 11
20) (-21) + 11 = -10
21) 8 + (-22) = -14
22) (-15) + 4 = -11
23) (-3) + 2 = -1
24) 17 + (-14) = 3
25) 17 + (-14) = 3
ĐỀ CƯƠNG ÔN TẬP TOÁN 6 I/ PHẦN SỐ HỌC 1/ Dạng toán thực hiện phép tính – tính nhanh nếu có thể - a) - 5/7 * 2/11 - 5/7 * 9/11 + 1 5/7 b) 11 3/13 - (2 4/7 + 5 3/13) c) 2/7 * .5 * 1/4 - 2/7 * .3 * 1/4 d) 5/7 * 1/3 - 5/7 * 1/4 - 5/7 * 1/12 75\%-1 1 2 +0,5: 5 12 -( -1 2 )^ 2 e) f) 7 19 . 8 11 + 7 19 , 3 11 - 12 19 g) - 5/12 * 2/11 - 5/12 * 9/11 + 5/12 h) - 5/7 * 2/11 - 5/7 * 9/11 + 1 5/7 i) 6 7 + 5 8 :5- 3 16 .(-2)^ 2 j) 8.(-5).(-4).2 ; *) 2 3 + 1 3 .( -2 3 + 5 6 ); 2 3 k) 1) - 2/5 + (- 5/9 + 2/5) m) 17/13 - (4/13 - 11)
Tính M = 3/5+3/7- 3/11/ 4/5+4/7- 4/11
\(M=\left(\frac{3}{5}+\frac{4}{5}\right)+\left(\frac{3}{7}+\frac{4}{7}\right)-\left(\frac{3}{11}+\frac{4}{11}\right)\)
\(=\frac{7}{5}+1-\frac{7}{11}\)
\(\frac{12}{5}-\frac{7}{11}\)
\(=......t\text{ự}t\text{ính}nh\text{á}\)
\(=\frac{3}{5}+\frac{3}{7}-\frac{3}{11}+\frac{4}{5}+\frac{4}{7}-\frac{4}{11}\)
\(=\left(\frac{3}{5}+\frac{4}{5}\right)+\left(\frac{3}{7}+\frac{4}{7}\right)-\left(\frac{3}{11}+\frac{4}{11}\right)\)
\(=\frac{7}{5}+1-\frac{7}{11}\)
\(=\frac{12}{5}-\frac{7}{11}\)
\(=\frac{97}{55}\)
Spirit Of Yen Thanh Dong lừa làmTính bằng 2 cách.
A, (6/11 +5/11)* 3/7
B, 3/5 * 7/9 + 3/5 * 2/9
C, ( 6/7 - 4/7 ) : 2/5
D, 8/15 : 2/11 + 7/15 : 2/11
A.3/7
B.3/5
C.5/7
D.11/2
k hộ mình nha!