Упростите выражение

Question

Упростите выражение

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Answer 1

Решение на фото                                                               

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Answer 2

(1/(b-1)-1(b^2-b))*b/(b+2)-2b/(b^2-4)

1) 1/(b-1)-1(b^2-b)=(b-1)/b(b-1)=1/b
2) 1/b * b/(b+2) = 1/(b+2)
3) 1/(b+2) - 2b/(b^2-4)= 1/(b+2) - 2b/(b-2)(b+2)= b-2-2b/(b-2)(b+2)= -2-3b/(b^2-4)