=> (x+3)2x.(x+3)= (x+3)2x.(x+3)3
=> (x+3)2x= (x+3)2x.(x+3)3:(x+3)
=> (x+3)2x.1= (x+3)2x. (x+3)2
=> 1=(x+3)2\(\Rightarrow\orbr{\begin{cases}\left(x+3\right)^2=1^2\\\left(x+3\right)^2=\left(-1\right)^2\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x+3=1\\x+3=\left(-1\right)\end{cases}}\Rightarrow\orbr{\begin{cases}x=\left(-2\right)\\x=\left(-4\right)\end{cases}}\)
\(\Rightarrow x=\left\{-2;-4\right\}\)
\(\Rightarrow\left(x+3\right)^{2x+1}-\left(x+3\right)^{2x+3}=0\)
\(\Rightarrow2x+1-2x+3=0\)
Mik quên cah làm rùi
đứa icewing gì đó làm sai rùi kết quả ra -2 mà
CMR : 1/72 - 1/74 + ... + 1/74n-1 - 1/74n + ... + 1/798 - 1/7100 < 1/50
Giúp mình với, mình cảm ơn.
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