Question

Determine a razão de uma pa na qual a8=-2 e a12=0

Answer 1

$a_8=-2\\a_{12}=0\\\\\\\displaystyle \mathsf{a_{12}=a_8+4r}\\\displaystyle \mathsf{0=-2+4r}\\\displaystyle \mathsf{4r=2}\\\\\displaystyle \mathsf{r=\dfrac{2}{4}\to0,5}$