-3-3...X=-75
75/3=25
-4+-6=-10
=> -4+(-6)^(25)=X
-3-3...X=-75
75/3=25
-4+-6=-10
=> -4+(-6)^(25)=X
Tìm x
1-4+7-10+...-x=-75
1. CMR:
a, 76 + 75 - 74 chia hết cho 11
b, 109 + 108 + 107 chia hết cho 112
2. CMR:
128 x 912 = 1816
7520 = 4510 x 530
3, Cho A = 3 + 32 + 33+...........+ 310.
Tìm số tự nhiên biết rằng 2A + 3 = 3n
+) A = ( 1,11 + 0,19 - 2,6 ) : ( 2,06 + 0,54 ) - ( \(\frac{1}{2}\) + \(\frac{1}{3}\) ) : 2
+) Tìm x :
a, (1,16 - x ) . 2,25 / 10 \(\frac{5}{9}\) - 7\(\frac{1}{4}\) . 2\(\frac{2}{11}\) = 75%
b) x + 25% .x = -1,25
c) x - 75% x = \(\frac{1}{4}\)
+) Tính nhanh nếu có thể :
a) 1\(\frac{1}{2}\) - 3\(\frac{3}{4}\) b) -8\(\frac{1}{6}\) - 7\(\frac{3}{2}\) c) 0,15 - 4,8 + 1,3 d) ( 2\(\frac{1}{3}\) + 3,5 ) : (-4\(\frac{1}{6}\) + 3\(\frac{1}{7}\) ) + 7,5
e) 11\(\frac{1}{4}\) + (2\(\frac{5}{7}\) + 5\(\frac{1}{4}\) ) f) \(\frac{4}{9}\) : ( \(\frac{1}{-7}\) + 6\(\frac{5}{9}\) :(-\(\frac{1}{7}\))
a) 1125-(374+1125)+(-65+374)
b)-23.65+23.21-58.23
c)-2003+(-21+75+2003)
d)942-2567+2563-1942
e)12-12+11+10-9_8-7+5-4+3+-1
Tìm x thuộc Z, biết
a, -5/7 + 1 + 30/-7 <_ x <_ -1/6 + 1/3 + 5/6
b, 1/2 - ( 1/3 + 1/4 ) < x < 1/48 - ( 1/16 - 1/6 )
c, ( x - 1/2 ) × ( x +3/4 ) < 0
d, 3/ ( x +2) ×( x +5) + 5/ ( x +5 ) × ( x+ 10) + 7/ ( x +10) ( x +17) = x / ( x+2) × ( x + 17)
Tìm x
A, | 2x - 1 | = | x + 3 |
B, ( 2x + 5 )^10 < ( x + 7 )^10
C, | x - 5 | < 4
D, | x + 7 | > 3
4(x-3) =7^2-1^10
Tìm x :
1/ |x-5|-7(x+4)=5-7x
2/3|x+4|-2(x+1)=7-2x
3/2|x-6|+7x-2=|x-6|+7x
4/|x+8|+(x-2)=5x-10:2
5/|x+2|-6(x-4)=20-6x
tìm x để :
a)-2+4+(-6)+8 +...+x=2014
b)1+(-4)+7+(-10)+...+(-x)=-3000