a, A = 110- (-761)+296+1454-(-813+1077)
b , B = 15.4^12.9^7-4.3^15.8^8/19.2^24.3^14-6.4^12.47^5
c , C = 2^50-2^49-2^48-2^47-...-2^2-2
1) 2 mũ 100 - 2 mũ 99 - 2 mũ 98 -...- 2 mũ 2 - 2 b
2)C= 110 - (761) + 296 - 1454 - ( 813 + 1077)
Các bạn giúp mk vs, mai mk cần rùi :)))
A= 110-(-761)+296-1454-(-813+1077)
A = 110-(-761) + 296 -1454 - (-813+1077)
A = 871 + 296 - 1454 - 264
A= -551
Tìm giá trị của B:
B=\(\frac{15.4^{12}.9^7-4.3^{15}.8^8}{19.2^{24}.3^{14}-6.4^{12}.27^5}\)
\(B=\frac{15.4^{12}.9^7-4.3^{15}.8^8}{19.2^{24}.3^{14}-6.4^{12}.27^5}=\frac{3}{1}=3\)
TÍNH NHANH
a) 5^4.3^4-(15^2-1)
b) 50^2-49^2+48^2-47^2+....+2^2-1^2
\(\frac{15.4^{12}.9^7-4.3^{15}.8^8}{19.2^{24}.3^{14}-6.4^{12}.27^5}\)
dấu "." là dấu nhân
giải đầy đủ hộ mình nhé
\(=\frac{3.5.\left(2^2\right)^{12}.\left(3^2\right)^7-2^2.3^{15}.\left(2^3\right)^8}{19.2^{24}.3^{14}-2.3.\left(2^2\right)^{12}.\left(3^3\right)^5}\)
\(=\frac{3.5.2^{24}.3^{14}-2^2.3^{15}.2^{24}}{19.2^{24}.3^{14}-2.3.2^{24}.3^{15}}\)
\(=\frac{5.2^{24}.3^{15}-3^{15}.2^{26}}{19.2^{24}.3^{14}-2^{25}.3^{16}}\)
\(=\frac{2^{24}.3^{15}.\left(5-2^2\right)}{2^{24}.3^{14}.\left(19-3^2\right)}\)
\(=\frac{3.1}{10}\)
\(=\frac{3}{10}\)
b) 49^6.5-7^11/(-7)^10.5+2.49^5
2^12.3^5-4^6.3^6/2^12.9^3+8^4.3^5
Tinh ti so a/b
A= 1/2+1/3+1/4+.....+1/48+1/49+1/50
B= 1/49+2/48+3/47+.....+48/2+49/1
1. Tính hợp lí nếu có thể :
a) 227+50+23 b)135+360+65+40 c)1+2+3+4+5...+97+98+99+100
d)115.13-13.15 e) 50-49+48-47+46-45...+4-3+2-1
f)30.40.50.60 g)27.36+27.64 h)5.22 - 18:3
i)13.17 - 256 : 16 +14:7-20210 j)72 -36:3
làm nhanh giúp mình vs chứ mình đang cần gấp
a) \(227+50+23=\left(227+23\right)+50=250+50=300\)
b) \(135+360+65+40=\left(135+65\right)+\left(360+40\right)=200+400=600\)
c) \(1+2+3+4+5+...+97+98+99+100\)
\(=\left(100+1\right)+\left(99+2\right)+...+\left(50+51\right)\)
\(=101+101+101+...+101\)
\(=101\cdot50\)
\(\Leftrightarrow5050\)
d) \(115\cdot13-13\cdot15=13\cdot\left(115-15\right)=13\cdot100=1300\)
e) \(50-49+48-47+...+4-3+2-1\)
\(=\left(50-49\right)+\left(48-47\right)+...+\left(2-1\right)\)
\(=1+1+1+1+..+1\)
\(=1\cdot25\)
\(=25\)
f) \(30\cdot40\cdot50\cdot60=10\cdot3+10\cdot4+10\cdot5+10\cdot6\)
\(=10\cdot10\cdot10\cdot10\cdot3\cdot4\cdot5\cdot6\)
\(=10000\cdot360\)
\(=3600000\)
g) \(27\cdot36+27\cdot64=27\cdot\left(36+64\right)=27\cdot100=2700\)
h) \(5\cdot2^2-18:3=5\cdot4-18:3=20-6=14\)
i) \(13\cdot17-256:16+14:7-2021^0\)
\(=13\cdot17-4^4:4^2+2-1\)
\(=13\cdot17-16+2-1\)
\(=13\cdot17-17\)
\(=17\cdot\left(13-1\right)\)
\(=204\)
j) \(7^2-36:3=49-12=37\)
Tính chuỗi các giá trị sau
a)1+3+5+7+...+45+47+49
b)2+4+6+8+...46+48+50
a.so so hang cua tong do la (49-1)/2+1=25
tong cac so hang do la (49+1)*25/2=625
b. lam tuong tu nhu cau a nha ban
a, Từ 1 đến 49 có: ( 49 - 1 ) : 2 + 1 = 25 ( số hạng )
1 + 3 + 5 + 7 + ... + 45 + 47 + 49
= ( 49 + 1 ) x 25 : 2
= 625
Từ 2 đến 50 có: ( 50 - 2 ) : 2 + 1 = 25 ( số hạng )
2 + 4 + ... + 50
= ( 50 + 2 ) x 25 : 2 = 650