A=1/2+1/2×2+1/2×2×2+…+1/2×2×2×2×2×2×2×2×2×2 12/10/2021 Bởi Quinn A=1/2+1/2×2+1/2×2×2+…+1/2×2×2×2×2×2×2×2×2×2
Đáp án: Giải thích các bước giải: A=1/2+1/2^2+1/2^3+…..+1/2^10 2 A=1+1/2+…..+1/2^9 2A-A=(1+…..+1/2^9) -(1/2+1/2^2+…..+1/2^10) A. =1-1/2^10 Bình luận
Bạn tham khảo : $A = \dfrac{1}{2} + \dfrac{1}{2.2} + \dfrac{1}{2.2.2} + … + \dfrac{1}{2 .2.2.2.2.2.2.2.2.2}$$A = \dfrac{1}{2} +\dfrac{1}{2^2}+\dfrac{1}{2^3} + …+\dfrac{1}{2^{10}}$ $\dfrac{1}{2}A = \dfrac{1}{2^2}+\dfrac{1}{2^3} +\dfrac{1}{2^4} …+\dfrac{1}{2^{11}}$ $\dfrac{1}{2}A – A =( \dfrac{1}{2^2}+\dfrac{1}{2^3} +\dfrac{1}{2^4} …+\dfrac{1}{2^{11}}) – ( \dfrac{1}{2} +\dfrac{1}{2^2}+\dfrac{1}{2^3} + …+\dfrac{1}{2^{10}})$ $ \dfrac{-1}{2}A = \dfrac{1}{2^{11}} – \dfrac{1}{2}$ $A = \dfrac{1}{2^{11}} – \dfrac{1}{2} + \dfrac{-1}{2}$ $A = \dfrac{1}{2^{11}} – (-1)$ $A = \dfrac{1}{2^{11}} +1$ Bình luận
Đáp án:
Giải thích các bước giải:
A=1/2+1/2^2+1/2^3+…..+1/2^10
2 A=1+1/2+…..+1/2^9
2A-A=(1+…..+1/2^9)
-(1/2+1/2^2+…..+1/2^10)
A. =1-1/2^10
Bạn tham khảo :
$A = \dfrac{1}{2} + \dfrac{1}{2.2} + \dfrac{1}{2.2.2} + … + \dfrac{1}{2 .2.2.2.2.2.2.2.2.2}$
$A = \dfrac{1}{2} +\dfrac{1}{2^2}+\dfrac{1}{2^3} + …+\dfrac{1}{2^{10}}$
$\dfrac{1}{2}A = \dfrac{1}{2^2}+\dfrac{1}{2^3} +\dfrac{1}{2^4} …+\dfrac{1}{2^{11}}$
$\dfrac{1}{2}A – A =( \dfrac{1}{2^2}+\dfrac{1}{2^3} +\dfrac{1}{2^4} …+\dfrac{1}{2^{11}}) – ( \dfrac{1}{2} +\dfrac{1}{2^2}+\dfrac{1}{2^3} + …+\dfrac{1}{2^{10}})$
$ \dfrac{-1}{2}A = \dfrac{1}{2^{11}} – \dfrac{1}{2}$
$A = \dfrac{1}{2^{11}} – \dfrac{1}{2} + \dfrac{-1}{2}$
$A = \dfrac{1}{2^{11}} – (-1)$
$A = \dfrac{1}{2^{11}} +1$