I need help
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- jayhawk2001
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You have to see the pattern hererajt wrote:Can you help me solve this?
(-1)^2*1/2 + (-1)^3*1/2^2 + ... + (-1)^11* 1/2^10
Take all positive and negative values separately
1/2 (1 + 1/2^2 + ... + 1/2^8 ) - 1/2^2 * (1 + 1/2^2 + ... + 1/2^8 )
= (1/2 - 1/4) * (1 + 1/2^2 + ... + 1/2^8 )
= 1/4 * (1 + 1/2^2 + ... + 1/2^8 )
This is greater than 1/4 but less than 1/2
Is it D ?