Download - a╳( a+b ) = a 2 +ab
Transcript
a╳(a+b) = a2+ab
a
a
a
b
a2
ab
a╳a
a╳b
a+b
a
b
a
c
a╳b
a╳c
ab
ac
a╳(b-c) = ab-ac
b-c
a b
c
d
ac bc
ad bd
(a+b)(c+d) = ac+ad+bc+bd6 3 24 46 3 26 342
54
24 12 12 6
54
9 6
98 199 1 1100 50
2 2
(100 2) (200 1)
20000 100 400 2
19502
1 1(100 ) (50 )
2 2
5000 50 251
4
15075
4
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