\(x.\left(x+1\right)=6\)
\(\Leftrightarrow2x+x=6\)
\(\Rightarrow3x=6\)
\(\Rightarrow x=2\)
\(x.\left(x+1\right)=6\)
\(\Leftrightarrow2x+x=6\)
\(\Rightarrow3x=6\)
\(\Rightarrow x=2\)
Tìm x
2.(x-5)-3(x+6)+=4(x-7)3(x-1)-2(x+5)=2(x-3)5(1-x)-6(1+x)=7(3-x)2x+5-3(3x+7)=6(1-x)+8x-2+3(x-4)=5(x-6)+7x+2+3(1-x)-5(2-x)=6(1-x)+(3-x)1 Tìm x:
a) 5.(1-x)-6.(1+x)=7.(3-x)
b) 2.(x+5)-3.(3x+7)=6.(1-x)+8x
c) x-2+3.(x-4)=5.(x-6)+7
d) x+2+3.(1-x)-5.(2-x)=6.(1-x)+7.(3x)
Bài 1: Tìm x :A) 3/4.(x-2) - 1/2.(6-2.x)= 1/6.x + 5
B) -1/2.(3.x + 5) - 2/3.(9-6.x) = 3/5.(x-10) - 3
C) (1/4.x - 1,5) + (5/6.x - 3) - (5/8.x -0,5) = -4,5
Tìm các số tự nhiên x sao cho các phân số sau là số tự nhiên : 1) 2/x 2) 3/x 3) 4/x 4) 5/x 5) 6/x 6) 9/x+1 7) 8/x+1 8) 7/x+1 9) 6/x+1 10) 5/x+1
A)4X(X-5)+X(X-1)
B)3X(6X-1)-X(X-6)
C)X(X-5)-X(X+3)-6(X+8)
D)Xmu2(X-2)-X(Xmu2-6)
giup minh voi=(
A= 1/2 x 3 + 1/3 x 4 + 1/4 x 5 + 1/5 x 6 + 1/6 x 7 + ... + 1/19 x 20
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)
a,x - 1/2 - (-1/6)
b,x + 5/6 = 3/8
c,2/3 . x -1/2 = 5/6
d, x/7 = 6/-21
e,(7/3 x -0,6) : 3^2/5 = 1
f,x/45 = 5/6 + -29/30
g,(4,5 - 2x) . (-1^4/7) =11/14
h,-2/7 + 4/7x=5/7
a, x+7=2 và 1/3 - (2x-2/3)
b,-7/6-x=1/6+5/6. x
c,x-30%x=-1 và 1/5
d, 4/3-(0,5+2/3x)=1/6