20232-2022.2023
Tính nhanh: 23+(27-7.6)-(94.7-27.99)
Câu 1: (4,5 điểm)
a) Tinh nhanh: 23 + (27 - 7.6) - (94.7 - 27.99)
mình ra 2023 có ai ra 2023 ko
ai có thì để lại cho mik 1 cái tích đúng nha
cảm ơn các bạn
tinh nhanh:16+(27-7.6)-(94.7-27.99)
Tính nhanh: 16 + (27-7.6) - (94.7-27.99)
16+(27-7.6)-94.7-27.99
=16+27-7.6-94.7-27.99
16+27(1+99)-7(6+94)=+2700-700=2016
đúng thì tk cho mk nha
2016 nha ban
Đáp án là 2016 bạn nha
bai 1 ]
A, tinh nhanh 16 + (27-7.6) - (94.7-27.99)
B, tinh tong A= 2/1.4 + 2/ 4.7+ 2/7.10 +.....+ 2/97.100
helps me !!!!!!!!!!!!! cac ban giup mik voi!!!!!!!!!!!!
\(A=\frac{2}{1.4}+\frac{2}{4.7}+\frac{2}{7.10}+...+\frac{2}{97.100}\)
\(A=2\left(\frac{1}{1.4}+\frac{1}{4.7}+\frac{1}{7.10}+...+\frac{1}{97.100}\right)\)
\(A=2\left(1-\frac{1}{4}+\frac{1}{4}-\frac{1}{7}+\frac{1}{7}-\frac{1}{10}+...+\frac{1}{97}-\frac{1}{100}\right)\)
\(A=2\left(1-\frac{1}{100}\right)\)
\(A=2.\frac{99}{100}=..............\)
Tự làm nốt nha
16+(27-6.7)-(94.7-27.99)
1.Tính nhanh:16+(27-7.6)-(94-7-27.99)
2.Tính tổng:A=\(\dfrac{2}{1.4}+\dfrac{2}{4.7}+\dfrac{2}{7.10}+...+\dfrac{2}{97.100}\)
1.
`16 + (27 - 7.6 ) - (94 -7 - 27.99)`
`= 16+ 27 - 7.6 - 94 + 7 + 27.99`
`= 16 + 27(99 +1) - 7(6-1) - 94`
`= -78 + 27.100 - 7.5`
`= 2587`
2.
`A = 2/1.4 + 2/4.7 + 2/7.10 +...+ 2/97.100`
`A= 2(1/1.4 + 1/4.7 + 1/7.10 +...+1/97.100)`
`3A = 2 (3/1.4 + 3/4.7 + 3/7.10+...+ 3/97.100)`
`3/2 A = 1 - 1/4 + 1/4 - 1/7 +...+ 1/97 - 1/100`
`3/2A = 1 - 1/100`
`3/2 A= 99/100`
`A= 99/100 : 3/2`
`A=33/50`
Vậy `A= 33/50`
1.16+(27-7.6)-(94-7-27.99)=16+27-7.6-94+7+27.99
=(27+27.99)+(27+7-94)+16
=27.100-60+16
=2700-44=2656
2.A=\(\dfrac{2}{1.4}+\dfrac{2}{4.7}+\dfrac{2}{7.10}+...+\dfrac{2}{97.100}\)
=\(\dfrac{1}{1}-\dfrac{1}{4}+\dfrac{1}{4}-\dfrac{1}{7}+...+\dfrac{1}{97}-\dfrac{1}{100}\)
=\(1-\dfrac{1}{100}=\dfrac{99}{100}\)
1) \(16+\left(27-7.6\right)-\left(94-7-27.99\right)\)
=\(16+27-7.6-94+7+27.99\)
=\(\left(27+27.99\right)+\left(-7.6+7\right)+\left(16-94\right)\)
=\(27\left(1+99\right)+7\left(-6+1\right)-78\)
=\(27.100-7.5-78=2700-35-78=2587\).
2) \(A=\dfrac{2}{1.4}+\dfrac{2}{4.7}+\dfrac{2}{7.10}+...+\dfrac{2}{97.100}\)
\(A=\dfrac{2.3}{1.4.3}+\dfrac{2.3}{4.7.3}+\dfrac{2.3}{7.10.3}+...+\dfrac{2.3}{97.100.3}\)
\(A=\dfrac{2}{3}.\left(\dfrac{3}{1.4}+\dfrac{3}{4.7}+\dfrac{3}{7.10}+...+\dfrac{3}{97.100}\right)\)
\(A=\dfrac{2}{3}.\left(\dfrac{1}{1}-\dfrac{1}{4}+\dfrac{1}{4}-\dfrac{1}{7}+\dfrac{1}{7}-\dfrac{1}{10}+...+\dfrac{1}{97}-\dfrac{1}{100}\right)\)
\(A=\dfrac{2}{3}.\left(\dfrac{1}{1}-\dfrac{1}{100}\right)=\dfrac{2}{3}.\dfrac{99}{100}=\dfrac{33}{50}\)
Cho A=3/22+8/32+15/42+....+20232-1/20232 Không là số tự nhiên (lm nhanh giúp mik vs ạ )
Tính nhanh: 20232 - 20222
\(2023^2-2022^2=\left(2023-2022\right)\left(2023+2022\right)\)
\(=1\cdot4045=4045\)
$2023^2-2022^2$
$=(2023-2022)(2023+2022)$
$=4045$
Tính nhanh : 48/41 + 45/27 + 34/28 + 37/23 - 18/27 - 6/28 - 7/41 - 14/23
48/41 + 45/27 + 34/28 + 37/23 - 18/27 - 6/28 - 7/41 - 14/23
= (48/41 - 7/41) + (45/27 - 18/27) + (34/28 - 6/28) + (37/23 - 14/23)
= 1 + 1 + 1 + 1
= 4