Insert 4 Gm.s between 2 and 486
2, _, _, _, _, _ 486
the question is simply asking us to construct a geometric sequence with : first term = 2, sixh term = 486
Yes , is the common ration of any GP = \[\huge [\frac{ b }{ a }]^{\frac{ 1 }{ n+1 }}\]
i don't like memorizing a formula for such a simple thing, but the formula would be : \[\huge [\frac{ b }{ a }]^{\frac{ 1 }{ n\color{Red}{-}1 }}\]
in book it is given n+1
lets derive it :)
Okay...
we're given below : first term = a nth term = b
nth term of geometric sequence is given by : \[\large b = ar^{n-1}\]
oh got it
isolate \(\large r\) ^^
once you have the value of \(r\), you can find the 2nd,3rd,4th and 5th terms
so it is just manipulating terms , but the answer is 6 ,18 , 54 ,162
thats right !
first term = 2 6th term = 486 so, \[\large 486 =2*r^{6-1}\]
\[\large 243 =r^{5}\]
\[\large r=3\]
multiply the first term by \(3\) to get second term multiply the second term by \(3\) to get third term and so on...
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