Cho A=1/2^2+1/3^2+1/4^2+.......+1/20^2 .Chung to rang A<1
Cho A=1/2^2+1/3^2+1/4^2+........+1/20^2 .Chung minh A<1
Chu thich / La phan so
^ la mu
Cho A=1/3^2+1/4^2+1/5^2+...+1/50^2
Chung to rang a,A>1=4 b,A>4/9
Cho A=1/3^2+1/4^2+1/5^2+...+1/50^2
Chung to rang a,A>1=4 b,A>4/9
Cho A=1/3^2+1/4^2+1/5^2+...+1/50^2
Chung to rang 1/4<M<4/9
Cho A=1/3^2+1/4^2+1/5^2+...+1/50^2
Chung to rang 1/4<M<4/9
Cho A=1/3^2+1/4^2+1/5^2+...+1/50^2
Chung to rang 1/4<M<4/9
chung minh rang A la 1 luy thua cua 2 voi A=A+2^2+2^3+2^4+...+2^20
sai đề rồi bn ơi A=A+2^2+2^3+2^4+...+2^20= ko ra kq nka
nếu đúng thì k , chúc bn hc tốt
a,A=1/1^2+1/2^2+1/3^2+1/4^2+...+1/50^2.chung minh rang a<2
b;2^1+2^2+2^3+...+2^30.chung minh rang B chia het cho21
cho A= 1/2+1/3+1/4+....+1/16. Chung to rang A khong la so tu nhien
A=1/2+3/4+5/6+........+199/200
chung to rang A^2<1/200