Question

como faz essas contas ?

Answer 1

(3a-4b)²
(3a)² + 2(3a)(-4b) + (-4b)²
 9a² - 24ab + 16b² 
a³-xy²= a6- 2a³xy+ x² y²

Answer 2

          (3A - 4B)² =
          (3A)² - 2.(3A).4B) + (4B)² =
           9A²  - 24AB + 16B²

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         (A³ - XY)² =
         (A³)² - 2.(A³).(XY) + (XY)² =
          A⁶   -  2A³XY       +  X²Y²
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          (X + Y)² =
           X² + 2XY + Y²