Ta có:
11111111-2222= 11108889
Mà: \(\sqrt{11108889}\)=3333
Có nghĩa:3333.3333= 11108999= 11111111-2222
=> Hiệu trên là 1 lũy thừa
C=3+3^2+3^3+3^4+.............+3^60
chung minh C+3 la 1 luy thua cua 3
C=3+3^2+3^3+3^4+.............+3^60
chung minh C+3 la 1 luy thua cua 3
Cho ababab la so co sau chu so, chung to so ababab la boi cua 3
P/s:Giai cho vui nha, toan 6 day hihi
cho m va n la cac so tu nhien , m la so le . Chung to m va mn +8 la 2 so nguyen to cung nhau
cho STN n. chung to rang 3n+2 va 5n+3 la hai so nguyen to cung nhau
voi gia tri nao cua x thuoc Z cac phan so sau co gia tri la 1 so nguyen
d.D= \(\dfrac{x^2-1}{x+1}\)
chung minh cac ps sau day la toi gian
b, \(\dfrac{n-1}{n-2}\)
Chung to rang voi moi so tu nhien n thi tich (n+4) * (n+7) la mot so chan
chung minh rang
7*n + 10 va 5*n + 7 la hai so nguyen to cung nhau
Ve hai goc ke bu xOy va yOz, biet goc xOy= 60o
a) Tinh so do goc yOt
b) Ot la tia phan giac cua goc xOy, Om la tia phan giac cua goc yOt. Chung to goc tOm la goc vuong.
