Tính theo cách hợp lý
a) (10^2+11^2+12^2):(13^2+14^2)
b)1.2.3....9 -1.2.3...8-1.2.3...7.8^2
c)(3.4.2^16)^2 /11.2^13.4^11-16^9
\(\text{Thực hiện các phép tính sau một cách hợp lý:}\)
\(a\)) \(\left(10^2+11^2+12^2\right):\left(13^2+14^2\right)\)
\(b\)) \(1.2.3...9-1.2.3...8-1.2.3...7.8^2\)
\(c\)) \(\dfrac{\left(3.4.2^{16}\right)^2}{11.2^{13}.4^{11}-16^9}\)
\(d\)) \(1152-\left(374+1152\right)+\left(-65+374\right)\)
\(e\)) \(13-12+11+10-9+8-7-6+5-4+3+2-1\)
Thuc hien cac phep tinh sau một cách hợp lí:
a) (10^2 + 11^2 + 12^2) : (13^2 + 14^2)
b) 1.2.3...9-1.2.3...8-1.2.3...7.8^2
c) (3.4.2^16)^2/11.2^13.4^11-16^9
d) 1152 - (374 + 1152) +(-65 + 374)
e) 13-12+11+10-9+8-7-6+5-4+3+2-1
a)(10^2+11^2+12^2):(13^2+14^2) b)1.2.3...9-1.2.3...8-1.2.3...7.8^2 c)(3.4.2)^16/11.2^13.4^11-16^9 d)1152-(374+1152)+(-56+374) e)13-12+11+10-9+8-7-6+5-4+3+2-1 |
Thực hiện các phép tính;
a, A=1+2+2^2+2^3+...+2^2018
b,B=1.2.3...9-1.2.3...8-1.2.3...7.8^2
c,C=(3.4.2^16)^2/11.2^13.4^11-16^9
thôi minh giai duoc roi .thanks ban nhieu
thực hiện các phép tính sau một cách hợp lí:
a,\(\left(10^2+11^2+12^2\right):\left(13^2+14^2\right)\)
b,\(1.2.3...9-1.2.3...8-1.2.3...7.8^2\)
c,\(\frac{\left(3.4.2^{16}\right)^2}{11.2^{13}.4^{11}-16^9}\)
d,1152-(374+1152)+(-65+374)
e,13-12+11+10-9+8-7-6+5-4+3-2-1
a) =\(\left[\left(12+1\right)^2+\left(12+2\right)^2\right]:\left(13^2+14^2\right)\)
=1
b)=(1.2.3....8).(9-1-8)
=(1.2.3....8).0
=0
mik chỉ giải được zậy thôi.
t mik nha.
1) 1.2.3...9 - 1.2.3...8 - 1.2.3...7.82
2) \(\frac{\left(3.4.2^{16}\right)^2}{11.2^{13}.4^{11}-16^9}\)
3)13 - 12 + 11 + 10 - 9 + 8 - 7 - 6 + 5 -4 +3 +2 -1
Câu 1 dễ mà :
1.2.3...9 - 1.2.3...8 - 1.2.3...7.82
= 1.2.3...8.9 - 1.2.3...8.1 - 1.2.3...7.8.8
= 1.2.3...8.( 9 - 1 - 8 )
= 1.2.3...8.0
= 0
còn câu 2 và 3 thì sao
K ghi lại đề câu 2 nha :
\(=\frac{3^2.\left(2^2\right)^2.2^{32}}{11.2^{13}.\left(2^2\right)^{11}-\left(2^4\right)^9}\)
\(=\frac{3^2.2^4.2^{32}}{11.2^{13}.2^{22}-2^{36}}\)
\(=\frac{3^2.2^{36}}{11.2^{35}-2^{35}.2}\)
\(=\frac{3^2.2^{36}}{2^{35}\left(11-2\right)}\)
\(=\frac{3^2.2^{36}}{2^{35}.3^2}\)
\(=\frac{3^2}{3^2}.\frac{2^{36}}{2^{35}}\)
\(=1.2=2\)
Bài 1: Thực hiện các phép tính sau một cách hợp lý:
a) ( 102 + 112 + 122 ) : ( 132 + 142 )
b) 1.2.3...9 - 1.2.3...8 - 1.2.3...7.82
c) ( 3.4.216)2 / 11.213.411-169
d) 1152 - ( 374 +1152 ) + ( -65+374 )
e) 13 - 12 +11 +10 - 9 + 8 - 7 - 6 + 5 - 4 + 3 + 2 - 1
Bài 2: Tìm x biết:
a) (19x + 2.52) :14 = (13 - 8)2 -42
b) x + ( x+1) + ( x+2) +...+ ( x+30) = 1240
c) 11 - (-53+x) = 97
d) -(x+84) +213 = -16
Bài 1:
A,
(100+121+144)÷(169+196)
=365:365=1
B
,1.2.3...7.8.(9-1-8)
=1.2.3...7.8.0=0
C,
3^2.2^4.2^32/11.2^13.2^22-2^26
=3^2.2^36/11.2^35-2^36
=3^2.2^36/2^35-(11-2)
=9.2/9=2
D,
=1152-374-1152+(-65)+374
=(1152-1152)+(-374+374)+(-65)
=0+0+(-65)=-65
E,
=13-(12-11-10+9)+(8-7-6+5)-(4-3-2+1)
=13-0+0-0=13
Bài 2:
A,(19x+50)÷14=25-16
(19x+50)÷14=9
19x+50=126
19x=76
x=4
B,
31x+(1+2+3+...+30)=1240
31x+465=1240
31x=775
×=25
BÀI 2:
c)11-(-53+x)=97
=> x=97-11-53
=> x=33
K CHO MÌNH NHA
a, \(\left(10^2+11^2+12^2\right)\div\left(13^2+14^2\right)\\ \)
b,\(1.2.3.....9-1.2.3....8-1.2.3.....7.8^2\)
c, \(\frac{\left(3.4.2^{16}\right)^2}{11.2^{13}.4^{11}-16^9}\)
d, \(1152-\left(374+1152\right)+\left(-65+374\right)\)
a) Đặt \(A=\left(10^2+11^2+12^2\right)\div\left(13^2+14^2\right)\)
- Ta có: \(A=\left(100+121+144\right)\div\left(169+196\right)\)
\(\Leftrightarrow A=365\div365=1\)
Vậy \(A=1\)
b) Đặt \(B=1.2.3.....9-1.2.3.....8-1.2.3.....8^2\)
- Ta có: \(B=1.2.3.....8.\left(9-1\right)-1.2.3.....8^2\)
\(\Leftrightarrow B=1.2.3.....8.8-1.2.3.....8.8=0\)
Vậy \(B=0\)
c) Đặt \(C=\frac{\left(3.4.2^{16}\right)^2}{11.2^{13}.4^{11}-16^9}\)
- Ta có: \(C=\frac{3^2.4^2.2^{32}}{11.2^{13}.2^{22}-2^{36}}\)
\(\Leftrightarrow C=\frac{3^2.2^4.2^{32}}{11.2^{35}-2^{36}}\)
\(\Leftrightarrow C=\frac{3^2.2^{36}}{2^{35}.\left(11-2\right)}\)
\(\Leftrightarrow C=\frac{9.2^{36}}{2^{35}.9}\)
\(\Leftrightarrow C=2\)
Vậy \(C=2\)
d) Đặt \(D=1152-\left(374+1152\right)+\left(-65+374\right)\)
- Ta có: \(D=1152-374-1152-65+374\)
\(\Leftrightarrow D=\left(1152-1152\right)+\left(374-374\right)-65\)
\(\Leftrightarrow D=-65\)
Vậy \(D=-65\)
Tính:
a)102+112+122/132+142
b)1.2.3...9-1.2.3...8-1.2.3...7.82
c)(3.4.216)2/11.213.411-169
d)1152-(374+1152)+(-65+374)
e)13-12+11+10-9+8-7-6+5-4+3+2-1
Giúp mình càng nhanh càng tốt nhé!!! Thank nhìu!
a)\(\left(10^2+11^2+12^2\right)\div\left(13^2+14^2\right)\)
\(=\left(100+121+144\right)\div\left(169+196\right)\)
\(=365\div365\)
\(=1\)
b) \(1.2.3...9-1.2.3...8-1.2.3...8^2\)
\(=1.2.3...8\left(9-1-8\right)\)
\(=1.2.3...8.0\)
\(=0\)
d) \(1152-\left(374+1152\right)+\left(-65+374\right)\)
\(=1152-374-1152-65+374\)
\(=\left(1152-1152\right)-65+\left(374-374\right)\)
\(=0-65+0\)
\(=-65\)
e) \(13-12+11+10-9+8-7-6+5-4+3+2-1\)
\(=13-\left(12-11\right)+\left(10-9\right)+\left(8-7\right)-\left(6-5\right)-\left(4-3\right)\)\(+\left(2-1\right)\)
\(=13-1+1+1-1-1+1\)
\(=13+0+0+0\)
\(=13\)
c)\(\frac{\left(3.4.2^{16}\right)^2}{11.2^{13}.4^{11}-16^9}\)
\(=\frac{3^2.\left(2^2\right)^2.\left(2^{16}\right)^2}{11.2^{13}.\left(2^2\right)^{11}-\left(2^4\right)^9}\)
\(=\frac{3^2.2^4.2^{32}}{11.2^{13}.2^{22}-2^{36}}\)
\(=\frac{3^2.2^{36}}{11.2^{35}-2^{36}}\)
\(=\frac{9.2^{36}}{2^{35}\left(11-2\right)}\)
\(=\frac{9.2^{36}}{2^{35}.9}\)
\(=3\)