Question

16(x-2)la patrat - (x+3)la patrat=​

Answer 1

Răspuns:

= (3x-11)·(5x-5) = 15x²-70x+55

Explicație pas cu pas:

16(x-2)² - (x+3)² =​ ?

16(x-2)² - (x+3)² =​ [4(x-2)]² - (x+3)²

Folosim formula a²-b² = (a-b)· (a+b)

​ [4(x-2)]² - (x+3)² = (4x-8-x-3)·(4x-8+x+3) =

= (3x-11)·(5x-5) = 15x²-15x-55x+55 = 15x²-70x+55

sau :

16(x-2)² - (x+3)² =​ 16(x²-4x+4)-(x²+6x+9) =

= 16x²-64x+64 -x²-6x-9 = 15x²-70x+55