GEOMETRIC SEQUENCES A ball is dropped from a height of 12 feet and returns to a height that is one-half of the height from which it fell. The ball continues to bounce half the height of the previous bounce each time. How far will the ball have traveled when it hits the ground for the fifth time?
@eliesaab
h -> 1/2 h -> (^1/2)2 h->(1/2)^3 h ->(1/2)^4 h etc
let us call \( a =\frac 1 2\) and \( h=12\)
the first time it bounces it travels h, the second times it hits, it will have traveled \[ h + a h +a h\]
the second times it hits, it will have traveled \[ h+ a h + ah + a^2 h + a^2 h \]
the fifth times it hits it would have traveled\[ h + 2 ah + 2 a^2 h + 2a^3h + 2 a^4 h + 2 a^5 h \]
are you following me?
\[ h + 2 ah + 2 a^2 h + 2a^3h + 2 a^4 h + 2 a^5 h\\ h( 1 + 2a( 1 + a +a^2 +a^3 +a^4))\\ \]
\[ 1 + a +a^2 +a^3 +a^4 \] Do you know how to find the sum of a geometric series? http://openstudy.com/study#/updates/5807f8b1e4b012711f1652b2
I've never heard of this formula, sorry I left for a little to help my sister with her school
@eliesaab i'm back
is it 1.5 feet? @Directrix @Aleah54 @eliesaab @Kikuo @umerlodhi @YourBoyDusty @green @Living4Jesus @Astrophysics @pooja195
I'm pretty sure its .375 feet. For instance |dw:1476923008680:dw| For a mathematical way, you can say \[an= an_{-1} /2 --- a1=12\]
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