Question

Tính nhanh

\(101^2\)

97.103

\(77^2+23^2+77.46\)

\(105^2-5^2\)

Answer 1

a) \(101^2\)

\(=\left(100+1\right)^2\)

\(=100^2+2.100.1+1^2\)

\(=10000+200+1\)

\(=10200+1\)

\(=10201\)

b) \(97.103\)

\(=\left(100-3\right).\left(100+3\right)\)

\(=100^2-3^2\)

\(=10000-9\)

\(=9991\)

c) \(77^2+23^2+77.46\)

\(=77^2+77.46+23^2\)

\(=77^2+2.77.23+23^2\)

\(=\left(77+23\right)^2\)

\(=100^2\)

\(=10000\)

d) \(105^2-5^2\)

\(=\left(105-5\right)\left(105+5\right)\)

\(=100.110\)

\(=11000\)

Answer 2

lâu lắm r moi lên h24, tớ giúp bn nhé:

*101² = (100+1)² = 10⁴ + 2.100.1 +1² = 10201

*97.103= (100-3)(100+3) = 10² - 3² = 9991

* = 77² + 2.77.23 + 23² = (77+23)² = 10⁴