X +X *3+ X *6= 2,7
X * (1+3+6)=2,7(VÌ X=X*1 MÀ)
X*10=2,7
X=2,7:10 NHỚ **** TỚ NHA
X=0,27
Kết luân:x=0,27
X +X *3+ X *6= 2,7
X * (1+3+6)=2,7(VÌ X=X*1 MÀ)
X*10=2,7
X=2,7:10 NHỚ **** TỚ NHA
X=0,27
Kết luân:x=0,27
Tìm x biết \(\left(\frac{1}{1\times2}+\frac{1}{2\times3}+\frac{1}{3\times4}+\frac{1}{4\times5}+\frac{1}{5\times6}\right)\times10-x=0\)
\(y=\frac{1\times2\times3+2\times4\times6+4\times8\times12+8\times16\times24}{2\times3\times4+4\times6\times8+8\times12\times16+16\times24\times32}\frac{ }{ }\)
\(\frac{1\times2\times3\times4\times5}{2\times3\times4\times5\times6}\)
tính :\(\frac{1}{1\times2\times3}+\frac{1}{2\times3\times4}+\frac{1}{3\times4\times5}+\frac{1}{4\times5\times6}+\frac{1}{5\times6\times7}+\frac{1}{6\times7\times8}+\frac{1}{7\times8\times9}+\frac{1}{8\times9\times10}\)
Tính nhanh:\(\frac{1\times2\times3+2\times4\times6+3\times6\times9+4\times8\times12+5\times10\times15}{1\times3\times5+2\times6\times10+3\times9\times15+4\times12\times20+5\times15\times25}-\frac{1+2+3+2+4+6+3+6+9+4+8+12+5+10+15}{1+3+5+2+6+10+3+9+15+4+12+20+5+15+25}\)
P = \(2\times3+3\times4+4\times5+5\times6+...+99\times100\)
Tích sau tận cùng là chữ số nào ?
\(1\times2\times3\times4\times5\times6\times7\times8\times......\times1000\)
tính giá trị biểu thức: \(\frac{1\times2\times3}{1\times6\times8}\times\frac{6\times4\times5}{3\times2\times2\times10}\)
Tính nhanh: D=\(\frac{4}{2\times3\times4}+\frac{4}{3\times4\times5}+\frac{4}{4\times5\times6}+.......+\frac{4}{98\times99\times100}\)