Question

resolva a inequação (x+4)(x-4)<0​

Answer 1

Resposta:

OLÁ!!!

$x = + 4$

$x < - 4 \\ - 4 < x < 4 \\ x > 4$

For the interval x<-4x<−4:

Let's pick x=-5x=−5. Then, (-5+4)(-5-4)<0(−5+4)(−5−4)<0.

After simplifying, we get 9<09<0, which is false.

Descarta este intervalo..

For the interval -4<x<4−4<x<4:

Let's pick x=0x=0. Then, (0+4)(0-4)<0(0+4)(0−4)<0.

After simplifying, we get -16<0−16<0, which is true.

Mantén este intervalo..

For the interval x>4x>4:

Let's pick x=5x=5. Then, (5+4)(5-4)<0(5+4)(5−4)<0.

After simplifying, we get 9<09<0, which is false.

Descarta este intervalo..

$\boxed {\boxed { - 4 < x < 4 }}$