Question

1.Tính nhanh :

a) \(101^2\)

b)\(199^2\)

c)\(47.53\)

Answer 1

a)Ta có \(101^2\)=\(\left(100+1\right)^2\)=10000+200+1

=10201

b)\(199^2\)=\(\left(200-1\right)^2=40000-400+1\)=39601

c)47.53=\(\left(50-3\right)\left(50+3\right)=50^2-3^2\)=2500-9=2491

Answer 2

giải

(47.53)=(47+3)(53-3)

=50.50=2500

Answer 3

Answer 4

a) 101²=(100+1)=100²+2.100.1+1²=10000+200+1=10201

b)199²=(200-1)=200²-2.200.1+1²=40000-400+1=39601

c)47.53=(50-3)(50+3)=50²-3²=2500-9=2491

Answer 5

a) \(101^2=\left(100+1\right)^2=100^2+2.100.1+1^2=10201\)

b) \(199^2=\left(100+99\right)^2=100^2+2.100.99+99^2=39601\)

c) \(47.53=\left(50-3\right)\left(50+3\right)=50^2-3^2=2491\)

Answer 6

10201

39601

2491

Answer 7

a) 101²=(100+1)²=10000+200+1=10201

b) 199²=(200-1)²=40000-400+1=39601

c)47.53=(50-3)(50+3)=2500-9=2491