Question

Bài `3` Tính nhanh

`a,101^2-99^2`

`b,98.102`

`c,77^2+23^2+77.46`

Answer 1

\(a.101^2-99^2=\left(101+99\right)\left(101-99\right)=200.2=400\)

\(b.98.102=98.\left(100+2\right)=9800+196=9996\)

\(c,77^2+23^2+77.46=77^2+23^2+2.77.23=\left(77+23\right)^2=100^2=10000\)