25 + 24 +23 +...+ x+ ( x - 2 ) + ( x - 3 ) = 25
25+24+23+...+x+(x-2)+(x-3)=25
x + (x+1) + (x+2) + (x+3) + .... + 13 + 14 = 14
25 + 24 + 23 +...+ x + (x - 2) + (x – 3) = 25
-2x+15 < 3x - 17 < 19 -x
x+(x+1) + (x+2) + (x+3) + ... +13 +14 = 14
25 + 24 + 23 + ... + x + (x-2) + (x-3) = 25
tìm số nguyên x
1) x+(x+1)+(x+2)+(x+3)+...+13+14=14
2) 25+24+23+...+x+(x-1)+(x-2)=25
Tìm số nguyên x
a)-3.(2x+5)<3x-7<19-x
b. 25+24+23+...+x+(x-2)+(x-3)=25
bài 1:
a. S2 = 21+23+25+...+1001
b. S4 = 15+25+35+..+115
bài 2:
a. 2x-138= 23 .32
b. 5.(x+35) = 515
c. 814- ( x-305)=712
d. 20 - [ 7(x-3) +4] =2
e. 9x-1 =9
e. 5x-2 -32 = 24 - (28. 22 - 210 . 22)
\(\frac{x-25}{1979}-\frac{x-24}{1980}-\frac{x-23}{1981}-\frac{x-22}{1982}=\frac{x-1979}{25}-\frac{x-1980}{24}-\frac{x-1981}{23}-\frac{x-1982}{22}\)
Tìm số nguyên x biết 25+24+23+...+x=25