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I just read somwhere thatif cos a = cos dthen a=2n(pi)±d where 
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#1
Feb2512, 08:00 PM

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i just read somwhere that
if cos a = cos d then a=2n(pi)±d where n is integer So, if cos (b*ln (i/j))= cos (b (lni/j))=cos(b*ln(j/i)) can i write b*ln i/j = 2n(pi)±b*ln(j/i) or bln(j/i)+bln(i/j)=2n(pi) or 2n(pi)=0 b=n(pi)/(ln(i/j)ln(j/i))=n(pi)/(b*ln(i/j)) then replace b in cos(b*lni/j)=cos(n(pi))= ±1 I feel that something is wrong. But what? 


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Feb2512, 08:59 PM

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