Question

Đã trả lời bởi chuyên gia

Answer 1

$A = \frac{(3 x - 2) (x + 1) - (2 x - 5) . (x^{2} - 1)}{x + 1}, x \neq - 1 = \frac{(3 x - 2) (x + 1) - (2 x - 5) (x - 1) (x + 1)}{x + 1} = \frac{(x + 1) . [3 x - 2 - (2 x - 5) (x - 1)]}{x + 1} = 3 x - 2 - (2 x - 5) (x - 1) = 3 x - 2 - 2 x^{2} + 2 x + 5 x - 5 = - 2 x^{2} + 10 x - 7 x = \frac{1}{2} = > A = - 2 . {(\frac{1}{2})}^{2} + 10 . \frac{1}{2} - 7 = \frac{- 5}{2}$ .

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Answer 2

$A = \frac{(3 x - 2) (x + 1) - (2 x - 5) . (x^{2} - 1)}{x + 1}, x \neq - 1 = \frac{(3 x - 2) (x + 1) - (2 x - 5) (x - 1) (x + 1)}{x + 1} = \frac{(x + 1) . [3 x - 2 - (2 x - 5) (x - 1)]}{x + 1} = 3 x - 2 - (2 x - 5) (x - 1) = 3 x - 2 - 2 x^{2} + 2 x + 5 x - 5 = - 2 x^{2} + 10 x - 7 x = \frac{1}{2} = > A = - 2 . {(\frac{1}{2})}^{2} + 10 . \frac{1}{2} - 7 = \frac{- 5}{2}$ .

Answer 3

$A = {3 . \frac{1}{2} - 2) (\frac{1}{2} + 1) - (2 . \frac{1}{2} - 5) [{(\frac{1}{2})}^{2} - 1]} : (\frac{1}{2} + 1) A = - \frac{1}{2} . \frac{3}{2} - (- 4) . (- \frac{3}{4}) : \frac{3}{2} A = - \frac{1}{2} . \frac{3}{2} + 4 . (- \frac{3}{4}) : \frac{3}{2} A = - \frac{3}{8} + (- 3) . \frac{2}{3} A = - \frac{3}{8} + (- 2) A = - \frac{19}{8}$

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Answer 4

$A = {3 . \frac{1}{2} - 2) (\frac{1}{2} + 1) - (2 . \frac{1}{2} - 5) [{(\frac{1}{2})}^{2} - 1]} : (\frac{1}{2} + 1) A = - \frac{1}{2} . \frac{3}{2} - (- 4) . (- \frac{3}{4}) : \frac{3}{2} A = - \frac{1}{2} . \frac{3}{2} + 4 . (- \frac{3}{4}) : \frac{3}{2} A = - \frac{3}{8} + (- 3) . \frac{2}{3} A = - \frac{3}{8} + (- 2) A = - \frac{19}{8}$

mình gửi bạn bài giải nhé!

Answer 5

Tham khảo

$A = \frac{(3 x - 2) (x + 1) - (2 x - 5) (x ² - 1)}{x + 1} đ k : x # - 1 A = \frac{(3 x - 2) (x + 1) - (2 x - 5) (x - 1) (x + 1)}{x + 1} A = \frac{(x + 1) . [(3 x - 2) - (2 x - 5) (x - 1)]}{x + 1} A = \frac{(x + 1) (3 x - 2 - 2 x^{2} + 2 x + 5 x - 5)}{x + 1} A = \frac{(x + 1) (- 2 x^{2} + 10 x - 7)}{x + 1} A = - 2 x^{2} + 10 x - 7 T h a y x = \frac{1}{2} v à o A t a c ó : A = - 2 \times {(\frac{1}{2})}^{2} + 10 \times \frac{1}{2} - 7 = \frac{- 1}{2} + 5 - 7 = \frac{- 5}{2} V ậ y k h í x = \frac{1}{2} t h ì g i á t r ị c ủ a A l à \frac{- 5}{2}$

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Answer 6

Tham khảo

$A = \frac{(3 x - 2) (x + 1) - (2 x - 5) (x ² - 1)}{x + 1} đ k : x # - 1 A = \frac{(3 x - 2) (x + 1) - (2 x - 5) (x - 1) (x + 1)}{x + 1} A = \frac{(x + 1) . [(3 x - 2) - (2 x - 5) (x - 1)]}{x + 1} A = \frac{(x + 1) (3 x - 2 - 2 x^{2} + 2 x + 5 x - 5)}{x + 1} A = \frac{(x + 1) (- 2 x^{2} + 10 x - 7)}{x + 1} A = - 2 x^{2} + 10 x - 7 T h a y x = \frac{1}{2} v à o A t a c ó : A = - 2 \times {(\frac{1}{2})}^{2} + 10 \times \frac{1}{2} - 7 = \frac{- 1}{2} + 5 - 7 = \frac{- 5}{2} V ậ y k h í x = \frac{1}{2} t h ì g i á t r ị c ủ a A l à \frac{- 5}{2}$

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