If `S_p` denotes the sum of the series `1+r^p+r^(2p)+ tooo`and `S_(2p)` the sum of the series `1-r^p+r^(2p)- tooo,` prove that `S_+S_(2p)=2S_(2p)dot`

Explanation

Given that,

`S_p​=1+r^p+r^(2p)+......oo`

here `a=1,r=r^p`

So,

the sum of infinty is,

`=>S=a/(1-r)`

`=>S_p=1/(1-r^p)->(1)`

Similarly,

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