Question

Determinati xER pentru care sunt adevarate egalitatile(x-2)(x+2)=4-(x+1)(x-1)​

Answer 1

(a+b)(a-b)=a²-b²

(x-2)(x+2)=4-(x+1)(x-1)

x²-2²=4-(x²-1²)

x²-4=4-x²+1

2x²=5+4

2x²=9

x²=9/2

x=±√(9/2)

x=±3/√2

x=±3√2/2