~ Bạn tham khảo ~

Câu 2 :

` x^6 . x^2 = x^(6+2) = x^8`

`x^9 : x = x^(9-1) = x^8`

Chọn đáp án : ` B`

Câu 3 : 

`(x^2)^4 = x^(2xx4) = 2^8`

`x^8 : x^0 = x^8 : 1 = x^8`

Chọn đáp án : ` B`

Câu 4 :

$#Vịt vàng$

$\text{Câu 2:}$

`x^{6} . x^{2} = x^{6+2} = x^{8}`

$\Rightarrow$ `x^{9} : x = x^{8} (TM)`

$\Rightarrow$ $\text{Chọn B}$

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$\text{Câu 3:}$

`(x^{2})^{4} = x^{2.4} = x^{8}`

$\Rightarrow$ `x^{8} : x^{1} = x^{8} (TM)`

$\Rightarrow$ $\text{Chọn B}$

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$\text{Câu 4:}$

$\text{Kí hiệu như hình}$

Ta có: $\widehat{aOb}$ đối đỉnh với $\widehat{cOp}$

Mà : $\widehat{aOb}$ = $50^o$

$\Rightarrow$ $\widehat{cOp}$ = $50^o$

Ta có: $\widehat{aOb}$ + $\widehat{bOc}$ = $180^o$ (kề bù)

$\Rightarrow$ $50^o$+ $\widehat{bOc}$ = $180^o$

$\Rightarrow$ $\widehat{bOc}$ = $180^o$ - $50^o$

$\Rightarrow$ $\widehat{bOc}$ = $130^o$

Ta có: $\widehat{aOP}$ + $\widehat{cOP}$ = $180^o$ (kề bù)

$\Rightarrow$ $\widehat{aOP}$ + $50^o$ = $180^o$

$\Rightarrow$ $\widehat{aOP}$ = $180^o$ - $50^o$

$\Rightarrow$ $\widehat{aOP}$ = $130^o$

Ta có: $\widehat{dPn}$ đối đỉnh với $\widehat{OPm}$

Mà : $\widehat{OPm}$ = $100^o$

$\Rightarrow$ $\widehat{dPn}$ = $100^o$

Ta có: $\widehat{dPn}$ + $\widehat{nPm}$ = $180^o$ (kề bù)

$\Rightarrow$ $100^o$ + $\widehat{nPm}$ = $180^o$

$\Rightarrow$ $\widehat{nPm}$ = $180^o$ - $100^o$

$\Rightarrow$ $\widehat{nPm}$ = $80^o$

Ta có: $\widehat{dPO}$ + $\widehat{OPm}$ = $180^o$ (kề bù)

$\Rightarrow$ $\widehat{dPO}$ + $100^o$ = $180^o$ 

$\Rightarrow$ $\widehat{dPO}$ = $180^o$  - $100^o$

$\Rightarrow$ $\widehat{dPO}$ = $80^o$