(7^1997-7^1995):(7^1994.7)
tính: (7^1997 - 7^1995) : (7^1994.7)
Ta có : ( 71997 - 71995 ) : ( 71994 . 7 ) =
= ( 71997 - 71995 ) : 71995
= 71997 : 71995 - 71995 : 71995
= 72 - 1
= 49 - 1 = 48
tính:
a, (7\((7^1997-7^1995):(7^1994.7)\)
(7^1997-7^1995):(7^1994.7)
(2^8+8^3):(2^5.2^3)
a) 71995.(72-1):71995=72-1=49-1=48
b) [28+(23)3]:25+3=(28+29):28=28(1+2):28=1+2=3
rút gọn:
A=(71997-71995) : (71997 - 7)
( 7^1997 - 7^1995) : (7^1994 x 7)
\(\left(7^{1997}-7^{1995}\right)\div\left(7^{1994}\times7\right)\)
\(=\left(7^{1997}-7^{1995}\right)\div7^{1995}\)
\(=7^{1997}\div7^{1995}-7^{1995}\div7^{1995}\)
\(=7^2-1\)
\(=48\)
P/s tham khảo nha
= 48 =)))))))))))))))))
đáp án : 48
Tính
b, (71997-71995):(71994.7)
(71997-71995):(71994.7) = (71997-71995):71995 = 71997 : 71995 - 71995 : 71995 = 72 : 1 = 49
(71997-71995):(71994.7)
=(71997-71995): 71995
=71997:71995-71995:71995
=72:1
=49:1=49
CHÚC BẠN HỌC GIỎI!!
Mình nhầm:72:1đổi thành 72-1=49-1=48
Tính
\(\left(7^{1997}-7^{1995}\right):\left(7^{1449}.7\right)\)
\(\left(7^{1997}-7^{1995}\right):\left(7^{1994}\cdot7\right)\)
\(=7^{1995}\cdot\left(7^2-1\right):7^{1995}\)
\(=7^2-1\)
\(=49-1\)
\(=48\)
(71997-71995):(71994)(ai làm dc mình tick cho:D)
= 71997 : 71994 - 71995 : 71994
= 73 - 71
= 343 - 7
= 336
Nhanh len,mai la hét han rui,ai tra lỏi minh cho
( \(7^{1997}\)- \(7^{1995}\)) : ( 7.\(7^{1994}\))
\(\left(7^{1997}-7^{1995}\right):\left(7.7^{1994}\right)\\ =\left(7^{1997}-7^{1995}\right):\left(7^{1+1994}\right)\\ =\left(7^{1997}-7^{1995}\right):7^{1995}\\ =\left(7^{1997}:7^{1995}\right)-\left(7^{1995}:7^{1995}\right)\\ =\left(7^{1997-1995}\right)-1\\ =7^2-1\\ =48\)