Huỳnh Anh Phương
29/06/2018 at 01:53-
Nguyễn Mạnh Hùng 29/06/2018 at 02:22We have:
\(\dfrac{1}{a}.4=a\)
\(\Rightarrow a^2=4\Rightarrow a\in\left\{2;-2\right\}\)
\(\dfrac{1}{b}.9=b\Rightarrow b\in\left\{3;-3\right\}\)
\(\Rightarrow a+b\in\left\{5;-1;1;-5\right\}\)
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