Toán Lớp 6: a.2^100-(1+2+2^2+2^3+…+2^99)
b.169.2011^0-17.(83-1702:23+1^2012)+2^7:2^4
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Toán Lớp 6: a.2^100-(1+2+2^2+2^3+…+2^99)
b.169.2011^0-17.(83-1702:23+1^2012)+2^7:2^4
Comments ( 2 )
Đặt A=(1+2+2^2+2^3+…+2^98+2^99)
=>2A=2+2^2+2^3+2^4+…2^99+2^100
=>2A-A=2^100-1
=>2^100-(1+2+2^2+2^3+…+2^98+2^99)
=2^100-(2^100-1)
=1
b)169.2011^0-17.(83-1702:23+1^2012)+2^7:2^4
=169.1-17.(83-74+1)+2^3
=169-17.10+8
=169-170+8
=7