Tìm x
1.-9/46 - 4/1/23 : (3/1/4 - x : 3/5) + 2/8/23=1
2.(6/2/7 * x +3/7) : 2/1/5 - 3/7=-1
3.5/8/17 : x + (-1/17) : x + 3/1/17 : 17/1/3=4/17
4.1/1 * 4 + 1/4 * 7 + 1/7 * 10 + ...+ 1/x(x + 3)=6/19
Tìm x (X+1|4 -1|3):(2+1|6-1|4)=7|46 Chú ý a|b : là phân số
Tìm x thuộc N, biết :
[(46-32)^2-(54-42)^2].2.x-1872=0
(x-7)^7=(c-7)^8
1+2^3+3^3-4^2.x=20
TÌM X BIẾT
a,(X+1/4-1/3) CHIA (2+1/6-1/4)=7/46
b,13/45-(13/21+X)7/12=7/10
Tìm x
a) ( x + 1/4 -1/3 ) : ( 2+ 1/6 -1/4 ) = 7 /46
b) 13/15- ( 13/21 + x ) . 7 /12 =7/10
Tìm x
a) ( x + 1/4 - 1/3 ) : ( 2 + 1/6 -1/4 ) = 7/46
b) ( 2/5 - 1/x + 3/10 ) : ( 1/2 - 3/20 ) = 1và 1/2
Tìm x
a) ( x + 1/4 - 1/3) : ( 2 + 1/6 -1/4) = 7/46
b) ( 2/5 - 1/x + 3/10 ) : ( 1/2 - 3/20) = 3/2
1.Tính tổng
a, A= 1/2 + 1/6 + 1/12 +...+ 1/n x (n+1)
b, B= 1 x 2 x 4 + 1/4 +...+ 1/9 x 100
2.Cho A= 1/4 x 3/6 x 5/8 x...x 43/46 x 45/48
B= 2/5 x 4/7 x 6/9 x...x 46/49
a, So sánh A và B
b, Cmr A <1/133
3.Tìm số TN x biết,
a, 10 + x/ 17 + = 3/5
b, 40 + x/ 77 - x = 6/7
4. Tìm số TN a,b biết:
a/b = 24/26
a, BCNN(a,b) = 1092
5.Tính nhanh
a, A= (1 - 1 = 2) x (1 - 1 = 3) x (1 - 1 = 4) x...x (1 - 1 = 20)
b, B= (1/3 - 1) x (1/6 - 1) x (1/10 - 1) x (1/15 -1)
c, D= (1 + 6/8) x (1 + 6/18) x ( 1+ 6/30)
tìm x thuộc Z
\(\left(x+\frac{1}{4}-\frac{1}{3}\right):\left(2+\frac{1}{6}-\frac{1}{4}\right)=\frac{7}{46}\)