[7^1997 - 7^1995] : [7^1994.7]

=[7^1997 - 7^1995] : 7^1995

=7^1997 : 7^1995 - 7^1995 : 7^1995

=7^2 - 1

=48

nhớ k cho mình nhé

Thank 

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

(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

\(\left(7^{1997}-7^{1995}\right):\left(7^{1994}\cdot7\right)\)

\(=7^{1995}\cdot\left(7^2-1\right):7^{1995}\)

\(=7^2-1\)

\(=49-1\)

\(=48\)

\(\left(7^{1997}-7^{1995}\right)\div\left(7^{1994}\times7\right)\)

\(=\left(7^{1997}-7^{1995}\right)\div7^{1995}\)

\(=7^{1997}\div7^{1995}-7^{1995}\div7^{1995}\)

\(=7^2-1\)

\(=48\)

P/s tham khảo nha

= 48 =)))))))))))))))))

đáp án : 48

a ] bằng1

bằng 5 cơ