X x 6 - 1996 = 2324
X x 6 - 1996 = 2324
x =.......
x =.......
x =.......
X x 6 - 1996 = 2324
X x 6 =2324+1996
X x 6 =4320
x =4320:6
x =720
Xx6= 2324+1996
Xx6=4320
=> X=4320:6
X=720
X x 6 - 1996 = 2324
X x 6 = 2324 + 1996
X x 6 = 4320
X = 4320 : 6
X = 720
125^3-b^3
64m^2+n^2
324-9x^3
(x+3)^2
(x+2)6^3
\(\left(x+3\right)^2=x^2+6x+9\)
Tìm x:
a) X x 3 = 3654
b) 2015 + X = 2324
a) X x 3 = 3652
X= 3654:3
X = 1218
b) 2015 + X = 2324
X = 2324 – 2015
X = 309
x-10/1994+X-8/1996+X-6/1998/+ X-4/2000+X-2/2002=X-2002/2+X-2000/4+X-1998/6+X-1996/8+X-1994/10
(X -10/1994 -1) + (X-8/1996 - 1) + (X-6/1998 - 1)+ (X-4/2000 - 1) + (X-2/2002 - 1) = (X-2002/2 - 1) + (X-2000/4 - 1) + (X-1998/6 - 1) + (X-1996/8 - 1) + (X-1994/10 - 1)
=> x-2004/1994 + x-2004/1996 + x-2004/1998 + x-2004/2000 + x-2004/2002 = x-2004/2 + x-2004/4 + x-2004/6 + x-2004/8 + x-2004/1994
=> x-2004/1994 + x-2004/1996 + x-2004/1998 + x-2004/2000 + x-2004/2002 - x-2004/2 - x-2004/4 - x-2004/6 - x-2004/8 - x-2004/1994 = 0
=> (x - 2004)(1/994 + 1/1996 + 1/1998 + 1/2000 + 1/2002 + 1/2 + 1/4 + 1/6 + 1/8) = 0
Mà (1/994 + 1/1996 + 1/1998 + 1/2000 + 1/2002 + 1/2 + 1/4 + 1/6 + 1/8) \(\ne\)0
=> x - 2004 = 0
=> x = 2004
Vậy x = 2004
Sửa (x - 2004) (1/1994 + 1/1996 + 1/1998/+ 1/2000 + 1/2002 + 1/2 + 1/4 + 1/6+ 1/8 + 1/10)
= (x - 2004) (1/1994 + 1/1996 + 1/1998/+ 1/2000 + 1/2002 - 1/2 -1/4 - 1/6 - 1/8 - 1/10)
:)))
x-10/1994+x-8/1996+x-6/1998+x-4/2000+x-9/2002=x-2002/2+x-2000/4
+x-1998/6+x-1996/8+x-1994/10
x-10/1994+x-8/1996+x-6/1998+x-4/2000+x-9/2002=x-2002/2+x-2000/4
+x-1998/6+x-1996/8+x-1994/10
\(\frac{x-10}{1994}+\frac{x-8}{1996}+\frac{x-6}{1998}+\frac{x-4}{2000}+\frac{x-2}{2002}=\frac{x-2002}{2}+\frac{x-2000}{4}+\frac{x-1998}{6}+\frac{x-1996}{8}+\frac{x-1994}{10}\)
\(\left(\frac{x-10}{1994}-1\right)\)+\(\left(\frac{x-8}{1996}-1\right)\)+\(\left(\frac{x-6}{1998}-1\right)\)+\(\left(\frac{x-4}{2000}-1\right)\)+\(\left(\frac{x-2}{2002}-1\right)\)=\(\left(\frac{x-2002}{2}-1\right)\)+\(\left(\frac{x-2000}{4}-1\right)\)+\(\left(\frac{x-1998}{6}-1\right)\)+\(\left(\frac{x-1996}{8}-1\right)\)+\(\left(\frac{x-1994}{10}-1\right)\)
suy ra \(\frac{x-2004}{1994}\)+\(\frac{x-2004}{1996}\)+\(\frac{x-2004}{1998}\)+\(\frac{x-2004}{2000}\)+\(\frac{x-2004}{2002}\)=\(\frac{x-2004}{2}\)+\(\frac{x-2004}{4}\)+\(\frac{x-2004}{6}\)+\(\frac{x-2004}{8}\)+\(\frac{x-2004}{10}\)
suy ra \(\frac{x-2004}{1994}\)+\(\frac{x-2004}{1996}\)+\(\frac{x-2004}{1998}\)+\(\frac{x-2004}{2000}\)+\(\frac{x-2004}{2002}\)- \(\frac{x-2004}{2}\)- \(\frac{x-2004}{4}\)- \(\frac{x-2004}{6}\)- \(\frac{x-2004}{8}\)- \(\frac{x-2004}{10}\)=0
suy ra (x-2004) . ( \(\frac{1}{1994}\)+\(\frac{1}{1996}\)+\(\frac{1}{1998}\)+\(\frac{1}{2000}\)+\(\frac{1}{2002}\)-\(\frac{1}{2}\)-\(\frac{1}{4}\)-\(\frac{1}{6}\)- \(\frac{1}{8}\)- \(\frac{1}{10}\))=0
Vì \(\frac{1}{1994}\)+\(\frac{1}{1996}\)+\(\frac{1}{1998}\)+\(\frac{1}{2000}\)+\(\frac{1}{2002}\)-\(\frac{1}{2}\)-\(\frac{1}{4}\)-\(\frac{1}{6}\)- \(\frac{1}{8}\)- \(\frac{1}{10}\) khác 0
nên x-2004=0 suy ra x=2004
1-2+3-4+5-6+...+2323-2324 = ?
= -1 + (-1) + ... + (-1) [Có (2324 - 2) : 2 + 1 = 1162 số - 1]
= -1 . 1162
= -1162
x+4/1996 +x+2/999 +x+8/664 =-6