g1=2, gn+1 = 3gn, what is g4-g2?

in the geometric series where g subscript 1 =2 and g subscript (n+1) = 3g subscript n, what is g subscript 4 minus g subscript 2

HELP

3 Answers

Relevance
  • 1 decade ago
    Favorite Answer

    So it goes: 2, 6, 18, 54, ... because each term is multiplied by 3 to get the next term. g4 is 54 and g2 is 6 so g4 - g2 is 48

  • 1 decade ago

    I'm using [ ] to show subscripts

    g[1] = 2

    g[n+1] = 3g[n]

    Therefore we can find g[2], seeing that we know g[1]

    g[1+1] = 3g[1]

    g[2] = 3g[1] = 3*2 = 6

    Now we have to find g[4], but we must find g[3] in order to do that.

    g[3] = 3g[2] = 3*6 = 18

    g[4] = 3g[3] = 3*18 = 54

    therefore: g[4] - g[2] = 54 - 6 = 48

    That's your answer!

  • 1 decade ago

    dude....UR SCREWED!

Still have questions? Get your answers by asking now.