Question

A = (x + 1).(x + 4) ; qual alternativa representa o valor de A?

x² + 4x + 4
x² + 4x + 1
x² + x + 4
x² - 4x + 4
x² + 5x + 4

Answer 1

$\huge\boxed{\boxed{\boxed{\sf x {}^{2} + 5x + 4 }}}$

Basta multiplicar os termos de ambos os parênteses.

$\boxed{ \begin{array}{lr} \sf (x + 1) \cdot(x + 4) \\ \\ \sf x \cdot x + 4x + x + 4 \\ \\\sf x {}^{2} + 4x + x + 4 \\ \\ \boxed{\boxed{\boxed{\sf x {}^{2} + 5x + 4}}} \end{array} }$

Att: Nerd1990