Tính giá trị biểu thức : E = $2$ + $2^{2}$ + $2^{3}$ + $2^{4}$ + … + $2^{100}$ F = $1$ + $3^{1}$ + $3^{2}$ + $3^{3}$ + … + $3^{100}$ G = $5$

Tính giá trị biểu thức :
E = $2$ + $2^{2}$ + $2^{3}$ + $2^{4}$ + … + $2^{100}$
F = $1$ + $3^{1}$ + $3^{2}$ + $3^{3}$ + … + $3^{100}$
G = $5$ + $5^{3}$ + $5^{5}$ + $5^{7}$ + … + $5^{99}$
H = $(1 + 2 + 3 + … + 100)$. ($1^{2}$ + $2^{2}$ + $3^{2}$ + … + $100^{2}$).$(65.111 – 13.15.37)$

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  1. +) 2E =  $2^{2}$ +$2^{3}$ + …. +$2^{101}$

    => 2E – E =$2^{2}$ +$2^{3}$ + …. +$2^{101}$ – 2 – $2^{2}$ – $2^{3}$ – …. -$2^{101}$

    => E = $2^{101}$ – 2

    +) 3F = 3 + $3^{2}$ +$3^{3}$ + …. +$3^{101}$ – 

    => 3F – F = 3 + $3^{2}$ +$3^{3}$ + …. +$3^{101}$ – 1 – $3^{1}$ +$3^{2}$ + …. +$3^{100}$ 

    => 2F = $3^{101}$ + 2

    => F = $\frac{3^{101}}{2}$ + 1

    +) B.$5^{2}$ = $5^{3}$ + $5^{5}$ + … + $5^{101}$ 

    => 25B – B = $5^{3}$ + $5^{5}$ + … + $5^{101}$ – 5 – $5^{3}$ – $5^{5}$ – … – $5^{99}$ 

    => 24B = $5^{101}$ -5

    => B = $\frac{5^{101}-5}{24}$

    +) H = (1+2+3+ … +100)($1^{2}$+$2^{2}$+$3^{2}$ +…+$100^{2}$)(65.111-13.5.111)

    H = (1+2+3+ … +100)($1^{2}$+$2^{2}$+$3^{2}$ +…+$100^{2}$)(111.65-111.65)

    H = (1+2+3+ … +100)($1^{2}$+$2^{2}$+$3^{2}$ +…+$100^{2}$).0

    H = 0

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  2. $E=2+2^2+2^3+…+2^{100}$

    $⇒2E=2^2+2^3+2^4+…+2^{101}$

    $⇒2E-E=(2^2+2^3+2^4+…+2^{101})-(2+2^2+2^3+…+2^{100})$

    $⇒E=2^{101}-2$

    Vậy $E=2^{101}-2$

    $F=1+3^1+3^2+…+3^{100}$

    $⇒3F=3^1+3^2+3^3+…+3^{101}$

    $⇒3F-F=(3^1+3^2+3^3+…+3^{101})-(1+3^1+3^2+…+3^{100})$

    $⇒2F=3^{101}-1$

    $⇒F=\frac{3^{101}-1}{2}$ 

    Vậy $F=\frac{3^{101}-1}{2}$ 

    $G=5+5^3+5^5+…+5^{99}$

    $⇒25G=5^3+5^5+5^7+…+5^{101}$

    $⇒25G-G=(5^3+5^5+5^7+…+5^{101})-(5+5^3+5^5+…+5^{99})$

    $⇒24G=5^{101}-5$

    $⇒G=\frac{5^{101}-5}{24}$ 

    Vậy $G=\frac{5^{101}-5}{24}$ 

    $H=(1+2+3+…+100).(1^2+2^2+3^2+…+100^2).(65.111-13.15.37)$

    $=(1+2+3+…+100).(1^2+2^2+3^2+…+100^2).[65.111-(13.5).(3.37)]$

    $=(1+2+3+…+100).(1^2+2^2+3^2+…+100^2).(65.111-65.111)$

    $=(1+2+3+…+100).(1^2+2^2+3^2+…+100^2).0$

    $=0$

    Vậy $H=0$.

     

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