Question

упростите выражение

15b +   8b   *  7b+21

3-b    b^2-9       4

Answer 1

  15         8 * b      7 * b + 21        15        2 * b * 7 * (b + 3)      15        14 * b

------- + --------- * ------------- = -------- + ---------------------- = ------- + --------- =

 3 - b      b² - 9            4            3 - b       (b - 3) * (b + 3)       3 - b      b - 3

   14 * b - 15

= ---------------

        b - 3