pls solve and answer the question in detail.
If log45 = x and log56 = y, then
(A) log46 = xy                     (B) log64 = xy                  (C) log32 = 1 2 x y   -   1                    (D) log23 = 1 2 x y   -   1

log45=xlog56=yxy=log45 log56Use logab=logxblogxaxy=loga5loga4 loga6loga5xy=loga6loga4 Use converse of logab=logxblogxaxy=log46log46=xylog22 6=xyUse logam b==1mlogab12log2 6=xylog2 6=2xylog2 2×3=2xyUse logamn=logam+loganlog2 2+log23=2xy1+log23=2xylog23=2xy-1Use of logab=1logba1log32=2xy-1log32=12xy-1

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answer
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ANSWER IS BOTH (A) AND (C)
since through solving both logarithmic function we will get-
let, log45=x
      5=4x or 5=(22)x=22x    (equation one)
let, log56=y
       6=5y or 6=(22x)y=22xy (from equation one)
this can also be written as: 3x2=22xy
                                         3=22xy/21 ;which is equal to 22xy-1
                                      so,3=22xy-1
NOW CHECK THE OPTIONS
(A) log46=xy
      LHS- log226 = 1/2 log26 = 1/2 log222xy=1/2 x 2xy = xy   (since 6=22xyand logaab=b x logaa = b x 1 =b [PROPERTY-1])
      HENCE, LHS=RHS   
                                      CORRECT ANSWER
(B) log64=xy
     LHS-log622 = 2log22xy2 = 2 x 1/2xy= 1/xy   (since 6=22xy and 4=22 and logaba =1/b x logaa = 1/b x 1= 1/b [PROPERTY-2])
      HENCE, LHS IS NOT EQUAL TO RHS
                                       WRONG ANSWER
(C) log32=1/2xy-1
      LHS-log32= log22xy-12 = 1/2xy-1 x log22 = 1/2xy-1  (since in starting it was proved that 3 can be written as 22xy-1 and PROPERTY-2 
                                                                                        is also used)
      HENCE , LHS=RHS 
                                        CORRECT ANSWER

(D) log23 = 1/2xy-1
      LHS- log23 =log222xy-1 =2xy-1 x log22 = 2xy-1 x 1 = 2xy-1     (since 3 can be written as 22xy-1 and PROPERTY-1 is also used)
       HENCE, LHS IS NOT EQUAL TO RHS
                                       WRONG ANSWER




 
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