Question

12. Calcula:
P = $\sqrt{(x+8)^{2}=(x+9)(x+7)$

Answer 1

Resolución:

Sabemos que:

$(a + b)^{2} = a^{2} -2ab + b^{2}\\(x + a)(x+b)=x^{2}+(a+b)x+ab$

Luego:

P = $\sqrt{x^{2}+16x+64-(x^{2}+16x+63)}$

P = $\sqrt{x^{2}+16x+64-x^{2}+16x+63}$

∴ P = 1