\(7M=7+7^2+7^3+...+7^{101}\)
\(7M-M=\left(7+7^2+...+7^{101}\right)-\left(1+7+..+7^{100}\right)\)
\(6M=7^{101}-1\)
\(M=\frac{7^{101}-1}{6}\)
rut gon 1+7^2+7^3+7^4+...+7^99
rut gon 1 + 7 + 7^2 + ... +7^101
rut gon A=1+1^ 2+1^ 3+1^4+1^5+1^6+1^7+1^8+1^9+...+1^2012
rut gon P= 1+-3+5+-7+...+17+-19
5 - 2/3 + 1/5
co loi giay nua nha ai lam co loi giai minh thch 7 tich
rut gon 1*2*5+3*3*15+4*8*20+7*14*350/2*5*11+6*10+33+8*20*44+14*35*770
Rut gon
A = 10101 . ( 5 / 111111 + 5 / 222222 - 4 / 3 . 7 . 11 13 37 )
rut gon
a,3x(2x-7)-3x(4x-5)
b,(-7x+8)(-2x+3)-7x(2x-4)
c,(2x-3)(3x2-2x+4)-(2x-3)(3x+4)
d,(-2+7)(3x-6)-(4x-5)(2x-6)
Rut gon cac phan so
a) -21 / 49 ; 39 / -65
b ) 5 mu 4 . 7 mu 3 / 5 mu 5 . 7 mu 2 ; 2 mu 2 . 3 mu 5 . 5 / 2 mu 4 . 3 mu 4 . 5 mu 2
