\(\frac{1988.1986+1997+1995}{1997.1996-1995.1996}\)
Giai dum nhanh cho minh nha
Dau cham la phep nhan nhe
a.1995x1997-1/1996.1995+1994
d.1988.1916 +1997+1995/1997.1996-1995.1996
a: \(=\dfrac{1995\left(1996+1\right)-1}{1996\cdot1995+1994}\)
\(=\dfrac{1995\cdot1996+1995-1}{1996\cdot1995+1994}\)
\(=\dfrac{1995\cdot1996+1994}{1996\cdot1995+1994}=1\)
b: \(=\dfrac{1988\cdot1916+2\cdot1916}{1996\left(1997-1995\right)}\)
\(=\dfrac{1990}{2}=995\)
a.1995x1997-1/1996.1995+1994
d.1988.1916 +1997+1995/1997.1996-1995.1996
A=\(\frac{-1997.1996+1}{\left(-1995\right).\left(-1997\right)+1996}\)
Rút gọn A
Rút gọn
\(\frac{-1997.1996+1}{-1995.\left(-1997\right)+1996}\)
\(\frac{-1997.1996+1}{-1995.\left(-1997\right)+1996}=\frac{-1997.\left(1995+1\right)+1}{1995.1997+1996}\)
\(=\frac{-1997.1995-1997+1}{1995.1997+1996}\)
\(=\frac{-1997.1995-1996}{1995.1997+1996}\)
\(=\frac{-\left(1997.1995+1996\right)}{1995.1997+1996}\)
\(=-1\)
-32/27-(3.x-7/9)3=-24/27
cac banlam nhanh nha minh can gap
dau cham la dau nhan nhe
Ta có : \(\frac{-32}{27}-\left(3x-\frac{7}{9}\right)^3=\) \(\frac{-24}{27}\)
<=> \(-\left(3x-\frac{7}{9}\right)^3=\left(\frac{2}{3}\right)^3\)
<=> \(-\left(3x-\frac{7}{9}\right)=\left(\frac{2}{3}\right)\)
<=> x= \(\frac{1}{27}\) -------chỗ này tắt
Rút gon \(\frac{-1997.1996+1}{\left(-1995\right).\left(-1997\right)+1996}\)
rut gon con 1/-1995 vi rut gon 1996 ca tu va mau
rut gon -1997 ca tu va mau cung deu co vi vay sau khi rut gon cac so giong nh au thi phan so tren con 1/-1995
1,Rút gọn
\(\frac{-1997.1996+1}{\left(-1995\right).\left(-1997\right)+1996}\)
\(\frac{-1997.1996+1}{\left(-1995\right).\left(-1997\right)+1996}=\frac{-1997\left(1995+1\right)+1}{1995.1997+1996}\)
\(=\frac{-1997.1995+\left(-1997\right)+1}{1995.1997+1996}=\frac{-1997.1995+\left(-1996\right)}{1995.1997+1996}=-1\)
\(\dfrac{\left(-1997\right).1996+1}{\left(-1995\right).\left(-1997\right)+1996}=\dfrac{-1997\left(1995+1\right)+1}{1995.1997+1996}=\dfrac{-1997.1995+\left(-1997\right)+1}{1995.1997+1996}=\dfrac{-1997.1995+\left(-1996\right)}{1995.1997+1996}=-1\)
Tinh nhanh
3.25.8+4.37.6+2.38.12
Dau cham la dau nhan nhe cac ban
3.25.8+4.37.6+2.38.12
=24.25+24.37+24.38
=24.(25+37+38)
=24.100
=2400
chúc bạn học tốt :)!
3.25.8+4.37.6+2.38.12
=24.25+24.37+24.38
=24.(25+37+38)
=24.100=2400
mik nha
3.25.8+4.37.6+2.38.12
= 24 . 25 + 24 . 37 + 24 . 38
= 24( 25 + 37 + 38 )
= 25 .100
= 2500
Giai nhanh va dung giup e nhe :
Ap dung cac tinh chat cua phep cong va phep nhan de tinh nhanh :
c) 25 . 5 . 4 . 27 . 2
25 x 5 x 4 x 27 x 2
= ( 25 x 4 ) x ( 5 x 2 ) x 27
= 100 x 10 x 27
= 1000 x 27
= 27000
25 . 5 . 4 . 27 . 2 = ( 25 . 4 ) . ( 5 . 2 ) . 27 = 100 . 10 . 27 = 1000 . 27 = 27000
25x5x4x27x2
=(25x4)x(5x2)x27
=100x10x27
=27000