Until recently, few people went cycling , but ..over.. the last few years more bikes have..been... sold in britain ...than.....cars. Now approximately two millionare brought each year , the major-ity of ....which... are mountain bikes there are over 500 different models to choose ....from..... and the price vary enormously. The cheapest can be brought for under Σ200, ....although....you will need over Σ4.000 for a bike at the top than Σ350 are not recommended ...since.. they are very heavy and therefore not much fun to ride. furthermore, they often break because they are not very ...well... made. The more expensive models are ...also... lighter because they are made ..of... metals like aluminium.

(Khúc in nghiêng có sai không bạn???)

Until recently, few people went cycling , but ..(0)over... the last few years more bikes have..(1).been.. sold in britain ...(2)than.....cars. Now approximately two million are brought each year , the major-ity of ....(3).them... are mountain bikes there are over 500 different models to choose ....(4).one.... and the price vary enormously. The cheapest can be brought for under Σ200, ....(5).or...you will need over Σ4.000 for a bike at the top than Σ350 are not recommended ...(6)because... they are very heavy and therefore not much fun to ride. furthermore, they often break because they are not very ...(7)well... made. The more expensive models are ...(8)much... lighter because they are made ..(9)of... metals like aluminium.

thì làm công thức

:>

Ta có :

\(\widehat{A}+\widehat{B}+\widehat{C}+\widehat{D}=360^o\)

\(\Rightarrow\widehat{A}+\widehat{B}=360^o-\left(\widehat{C}+\widehat{D}\right)\)

\(\Rightarrow\widehat{A}+\widehat{B}=360^o-\left(60+80\right)=220^o\)

mà \(\widehat{A}-\widehat{B}=10^o\)

\(\Rightarrow\widehat{A}=\left(220-10\right):2=105^o\)

\(\Rightarrow\widehat{B}=105-10=95^o\)

Vậy \(\left\{{}\begin{matrix}\widehat{A}=105^o\\\widehat{B}=95^o\end{matrix}\right.\)

Giả sử \(c=min\left\{a,b,c\right\}\)\(VT-VP=(a-b)^2(2a^2bc+2ab^2c-abc^2+3ac^3+3bc^3)+(a-c) (b-c) (3 a^2b^2+2 a^2b c+2ab^2c+2abc^2)\ge0\)

Ủa nãy trong tin nhắn anh nhớ có điều kiện a, b, c > 0 mà? Sao tự nhiên xóa mất-_-

you've forgot

we have

\(\frac{2a}{a^2+c+1}\le\frac{2a}{2a+c}=1-\frac{c}{2a+c}=1-\frac{c^2}{2ac+c^2}\)