\(100-99+98-97+...+2-1\)
\(=\left(100-99\right)+\left(98-97\right)+...+\left(2-1\right)\)
\(=1+1+...+1\)
Có 50 số 1
\(=1.50\)
\(=50\)
\(100-99+98-97+...+2-1\)
\(=\left(100-99\right)+\left(98-97\right)+...+\left(2-1\right)\)
\(=1+1+...+1\)
Có 50 số 1
\(=1.50\)
\(=50\)
\(100-99+98-97+...+2-1\\ \)
\(=\left(100-99\right)+\left(98-97\right)+...+\left(2-1\right)\)
\(=1+1+...+1\)(50 số hạng 1)
\(=1.50\)
\(=50\)