(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

= 7¹⁹⁹⁷ : 7¹⁹⁹⁴ - 7¹⁹⁹⁵ : 7¹⁹⁹⁴

= 7³ - 7¹

= 343 - 7

= 336

Nhanh len,mai la hét han rui,ai tra lỏi minh cho

\(\left(7^{1997}-7^{1995}\right):\left(7.7^{1994}\right)\\ =\left(7^{1997}-7^{1995}\right):\left(7^{1+1994}\right)\\ =\left(7^{1997}-7^{1995}\right):7^{1995}\\ =\left(7^{1997}:7^{1995}\right)-\left(7^{1995}:7^{1995}\right)\\ =\left(7^{1997-1995}\right)-1\\ =7^2-1\\ =48\)

a. 3/5 + 6/11 + 7/13 + 2/5 + 16/11 + 19/13

 = ( 3/5 + 2/5 ) + ( 6/11 + 16/11 ) + ( 7/13 + 19/13)

 = 1 + 2 + 2

 = 5.

de om 5 chu may

vì 5/5+22/11+26/13=1+2+2=5

a) \(\frac{3}{5}+\frac{6}{11}+\frac{7}{13}+\frac{2}{5}+\frac{16}{11}+\frac{19}{13}\)

\(=\left(\frac{3}{5}+\frac{2}{5}\right)+\left(\frac{6}{11}+\frac{16}{11}\right)+\left(\frac{7}{13}+\frac{19}{13}\right)\)

\(=1+2+2=5\)

b) \(\frac{1995}{1997}x\frac{1990}{1993}x\frac{1997}{1994}x\frac{1993}{1995}x\frac{997}{995}=\frac{1995x1990x1997x1993x997}{1997x1993x1994x1995x995}=\frac{1990x997}{1994x995}=\frac{995x2x997}{997x2x995}=1\)

a) =(3/5+2/5)+(6/11+16/11)+(19/13+7/13)

=5/5+22/11+26/13

=1+2+3

=6

(7 mũ 1997 - 7 mũ 1995):(7 mũ 1994.7)=(7 mũ 1997 - 7 mũ 1995):7 mũ 1995=7 mũ 1997: 7 mũ 1995 - 7 mũ 1995 : 7mũ 1995= 7 mũ 2 -1=49-1=48

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

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

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

\(=7^2\div1\)

\(=49\div1\)

\(=49\)

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