a ] bằng1

bằng 5 cơ

(1-2-3+4)+(5-6-7+8)+.....+(1993-1994-1995+1996)+1997

=0+0+....+0+1997

=1997

1995 * 1994 - 1 / 1993 * 1995 + 1994

= 1995 * 1994 - 1 / ( 1994 -1 ) * 1995 + 1994

= 1995 * 1994 - 1 / 1994 * 1995 - 1995 + 1994

= 1995 * 1994 - 1 / 1994 * 1995 - 1

= 1

nhấn đúng cho mk nha

Tính nhanh giá trị biểu thức :

   1995 x 1994 - 1 / 1993 x 1995 + 1994

= 1995 x 1994 - 1 /  ( 1994 - 1 ) x 1995 + 1994

= 1995 x 1994 - 1 / 1994 x 1995 - 1995 + 1994

= 1995 x 1884 - 1 / 1994 x 1995 - 1

= 1

nè xem đi

phân số à

\(\frac{1995.1994-1}{1993.1995+1994}=\frac{1995\left(1993+1\right)-1}{1993.1995+1994}\)

\(\frac{1995.1993+1995-1}{1993.1995+1994}=\frac{1995.1993+1994}{1993.1995+1994}=1\)

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