-(-1/2)^2+0,25 :1/12
a,(1/2-2/3)^2
b,2:(1/2-2/3)^2
c,0,25^3.8^3
d,(-12)^4.6^4
e, 2:(1/2-2/3)^2+0,25^3.8^3-(-12)^4.6^4
(mai em thi rồi ạ)
60% - 2\(\dfrac{1}{2}\) - \(\dfrac{1}{4}\) - 0,25 : \(\dfrac{5}{12}\)
`60% - 2 1/2 - 1/4 - 0,25:5/12`
`=3/5-5/2-1/4-1/4 . 12/5`
`=3/5-5/2-1/4-3/5`
`=(3/5-3/5)-(5/2+1/4)`
`=0-(10/4+1/4)`
`=-11/4`
-1/1/12.(-3)^2-0,25: 5/8 + 75//100
B1: tính
A) 1/6-1/4+1/12
B)1/2-0,25+12
C) -3/8+(1/2-3/4)
a,\(\frac{1}{6}-\frac{1}{4}+\frac{1}{12}\)
\(=\frac{2}{12}-\frac{3}{12}+\frac{1}{12}\)
\(=0\)
\(b,\frac{1}{2}-0.25+12\)
\(=\frac{1}{2}-\frac{1}{4}+\frac{12}{1}\)
\(=\frac{2}{4}-\frac{1}{4}+\frac{48}{4}\)
\(=49\)
c, \(-\frac{3}{8}+\left(\frac{1}{2}-\frac{3}{4}\right)\)
\(=-\frac{3}{8}+\left(\frac{4}{8}-\frac{6}{8}\right)\)
\(=-\frac{5}{8}\)
RÚT GỌN
B= \(\frac{\left(1^4+0,25\right).\left(3^4+0,25\right).\left(5^4+0,25\right)....\left(11^4+0,25\right)}{\left(2^4+0.25\right).\left(4^4+0,25\right).\left(6^4+0,25\right).....\left(12^4+0,25\right)}\)
AI LÀM ĐÚNG CHO 2 TICK LUÔN
0,25 CÁC BẠN CHUYỂN THÀNH 1 PHẦN 4 NHA
\(\text{Xét công thức tổng quát }:x^4+\frac{1}{4}=\left(x^4+2.x^2.\frac{1}{2}+\frac{1}{4}\right)-x^2\)
\(=\left(x^2+\frac{1}{2}\right)^2-x^2=\left(x^2-x+\frac{1}{2}\right)\left(x^2+x+\frac{1}{2}\right)\)
Áp dụng vào B ta đc:
\(B=\frac{\left(1^4+\frac{1}{4}\right)\left(3^4+\frac{1}{4}\right)...\left(11^4+\frac{1}{4}\right)}{\left(2^4+\frac{1}{4}\right)\left(4^4+\frac{1}{4}\right)...\left(12^4+\frac{1}{4}\right)}\)
\(=\frac{\left(1^2-1+\frac{1}{2}\right)\left(1^2+1+\frac{1}{2}\right)\left(3^2-3+\frac{1}{2}\right)\left(3^2+3+\frac{1}{2}\right)...\left(11^2-11+\frac{1}{2}\right)\left(11^2+11+\frac{1}{2}\right)}{\left(2^2-2+\frac{1}{2}\right)\left(2^2+2+\frac{1}{2}\right)\left(4^2-4+\frac{1}{2}\right)\left(4^2+4+\frac{1}{2}\right)...\left(12^2-12+\frac{1}{2}\right)\left(12^2+12+\frac{1}{2}\right)}\)
\(=\frac{\frac{1}{2}\left(2+\frac{1}{2}\right)\left(6+\frac{1}{2}\right)\left(12+\frac{1}{2}\right)...\left(110+\frac{1}{2}\right)\left(122+\frac{1}{2}\right)}{\left(2+\frac{1}{2}\right)\left(6+\frac{1}{2}\right)\left(12+\frac{1}{2}\right)\left(20+\frac{1}{2}\right)...\left(132+\frac{1}{2}\right)\left(156+\frac{1}{2}\right)}\)
\(=\frac{\frac{1}{2}\left(122+\frac{1}{2}\right)}{\left(132+\frac{1}{2}\right)\left(156+\frac{1}{2}\right)}=\frac{49}{16589}\)
ko biết có đúng ko!! hình như còn 1 cách là nhân 1 đa thức với 16 nữa thì phải lâu ko động đến bạn thử xem đc ko nhé
a)2/9-(-4/9)=
b)(-1/24+0,25+1 1/12):(-1/2)2
c)3/13.-5/9+10/13.-5/9+-4/9
Bài 2:
a)-4 1/5:x=5 1/4, b)7/12-5/12.x=1/12
a)2/9-(-4/9)=6/9=2/3
b)(-1/24+0,25+1 1/12):(-1/2)2
=(-1/24+6/24+26/24):(-1/2).2
=31/24.-2.2
=-31/12.2
=-31/6
c)3/13.(-5/9)+10/13.(-5/9)+(-4/9)
=-5/9(3/13+10/13)+(-4/9)
=-5/9.1+(-4/9)
=-1
1.
a)2/9-(-4/9)=6/9
b)(-1/24+0,25+11/12):(-1/2)2
=1,125:-1
=-1,125
c) 3/13.-5/9+10/13.-5/9+-4/9
=-5/9.(3/13+10/13)+4/9
=5/9.1+4/9
=5/9+4/9
=9/9=1
2.
a)-41/5:x=51/4
x=51/41.-41/5
x=-1
vậy x=-1
b)7/12-5/12.x=1/12
5/12.x=1/12+7/12
5/12.x=6/12
x=6/12:5/12
x=6/12.12/5
x=6/5
vậy x=6/5
Tính nhanh (nếu có):
1) 2/3 + -3/7 + -7/10 + 3/-8
2) 7+ ( 7/12 - 1/12 + 3) - (1/12 + 5)
3) 3/4 - 0,25 - [ 7/3 + (-9/2)] - 5/6
Sắp xếp theo thứ tự tăng dần : -0,25 ; 1/2 ; -0,5 ; 5/6 ; 13/12 ; -5/24 ; 0 ; 1/48 ; 2/3 ; -9/8 .
Sắp xếp: \(-\dfrac{9}{8};-0,5;-0,25;-\dfrac{5}{24};0;\dfrac{1}{48};\dfrac{1}{2};\dfrac{2}{3};\dfrac{5}{6};\dfrac{13}{12}\)
Tính nhanh
( 1/2 + 25 % + 0,5 + 3/4 + 0,25 + 75 % ) x ( 2 4/10 + 3 9/15 ) / ( 7/4 - 0,25 ) x 12
làm cách giải ra cho mình nhé