For what positive value of p will this be a geometric sequence: p-3, p+1, 3p+3?

Question

For what positive value of p will this be a geometric sequence: p-3, p+1, 3p+3?

1 Answer

Impact of this question

1741 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-01-16T13:43:18

$p = 5$ $p=5$

Explanation:

If $p - 3, p + 1, 3 p + 3$ $p-3, p+1, 3p+3$ is a geometric sequence
then for some constant $c$ $c$ :
$XXX (p - 3) \times c = (p + 1)$ $color(white)("XXX")color(red)((p-3)xxc=(p+1))$
and
$XXX (p + 1) \times c = 3 p + 3$ $color(white)("XXX"color(blue)((p+1)xxc=3p+3)$

Therefore
$color(white)("XXX")color(blue)(((p+1)xxcancel(c)))/color(red)(((p-3)xxcancel(c)))=color(blue)((3p+3))/color(red)((p+1))=(3(cancel(p+1)))/(cancel(p+1))$

$color(white)("XXX")(p+1)/(p-3)=3$

$color(white)("XXX")p+1=3p-9$

$color(white)("XXX")-2p=-10$

$color(white)("XXX")p=5$

Science

Math

Humanities

... and beyond

For what positive value of p will this be a geometric sequence: p-3, p+1, 3p+3?

1 Answer

Explanation:

Related questions

Impact of this question