Question

Qual a função f(×)=-2×^2+4×-1​

Answer 1

$f(×)=- {2x}^{2} + 4× - 1 \\ f(×)=-2( {x}^{2} - 2x) - 1 \\ f(×) + ? = - 2( {x}^{2} - 2x + ?) - 1 \\ f(x) + ? = - 2( {x}^{2} - 2x + 1) - 1 \\ f(x) - 2 \times 1 = - 2( {x}^{2} - 2x + 1)- 1 \\ f(x) - 2 = - 2(x - 1)^{2} - 1 \\ f(x) = - 2(x - 1)^{2} - 1 + 2 \\ f(x) = - 2(x - 1)^{2} + 1$