Tập nghiệm của bất phương trình  x + 2 x + 2 2 + 3 + + x x 2 + 3 + 1 > 0 là

A.  1 ; 2

B. - 1 ; 2

C. - 1 ; + ∞

D. 1 ; + ∞

Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.

Helen Killer, who was both blind and deafness, overcame her inabilities with the help of her teacher, Ann Sulivan

A. who

B. blind

C. deafness

D. inabilities

nước đá

\(a^2=b.c\Rightarrow\frac{a}{b}=\frac{c}{a}\)

=> \(\frac{a}{c}=\frac{b}{a}=\frac{a+b}{c+a}=\frac{a-b}{c-a}\Rightarrow\frac{a+b}{a-b}=\frac{c+a}{c-a}\left(đpcm\right)\)

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