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ritwalok (22)

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-1=i & i^i=e^(-pi/2) . i is imaginary no. i^i which is imaginary raise to imaginary ,then how it is a very large real no.
    
kghedriu (2333)

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say f(x)= e^(sin-1x) ....it is e to the power of sin inverse x...
 
now... f(1/2)= e^pi/6 and f(-1/2)= e^-pi/6
cubing this....we get e^pi/2 or e^-pi/2 in RHS.....
 
by expansions...
 
f(x)= 1+x+ x^2/2! +2x^3/3!+ 5x^4/4!+.......
 
     ={1 +t 2k+1}+ {x+t 2k+2}  where k runs frm 1 to infinity and mod x less dan 1..
 
and t2k+1= (1)(2^2+1)(4^2+1).....[(2k-1)^2+1]x^2k/(2k)!
 
and
t 2k+2 = (1^2+1)(3^2+1)........x^2k+1/(2k+1)!
now...use these formulas to calculate 85 terms in each with each term rounded to 54 decimal places..this processs gives  fifty two decimal places of e^pi/6
 
simly calc for e^-pi/6
 
den multiply to get e ^-pi/3
calc e^-pi/3
multiply to get e^-pi/2 which is LHS and i^i is our RHS
 
this is the only way to do this...
it was given in 1922 by UHLER....
 
finally the value of i^i is as follows...
 
0.2078795763
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elessar_iitkgp (2326)

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i = cos/2 + i sin/2 = ei/2
ii = (ei/2)i = e-/2 (As i2 = -1)
 = 1/e/2
Now e lies between 2 and 3.
/2 is approximately = 1.57
Hence e/2 isn't a very large value. Infact it will be less than 6 but definitely greater than 1.
Hence its reciprocal 1/e/2 should be less than unity
And hence ii is a real number less than unity.

Please check the question. It shouldn't be a large real number.



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