Logarithm


  1. If 100.3010 = 2, then find the value of log0.125 125. ?









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    Exp. = log0.125125 = log2-3 53 = - 3/3log25 = -log25
    ∵ 100.3010 = 2
    ⇒ log102 = 0.3010
    ∵ log105 = log1010/2 = log1010-log102
    = 1-0.3010 = 0.6990

    Correct Option: B

    Exp. = log0.125125 = log2-3 53 = - 3/3log25 = -log25
    ∵ 100.3010 = 2
    ⇒ log102 = 0.3010
    ∵ log105 = log1010/2 = log1010-log102
    = 1-0.3010 = 0.6990
    ∴ -log25 = - log105 / log102
    = - 0.6990 / 0.3010 = - 699/301


  1. Find the value of log0.125 64 ?









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    Exp. = log0.12564 = log2-3 26
    ={6 / (-3)} log22

    Correct Option: D

    Exp. = log0.12564 = log2-3 26
    ={6 / (-3)} log22
    = -2



  1. Find the value of log3228 + log24337 - log361296 ?









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    Exp. =log3228 + log24337 - log361296
    = log25 28 + log35 37 - log36 362
    = (8/5)log22 + (7/5)log33 - 2log3636

    Correct Option: C

    Exp. =log3228 + log24337 - log361296
    = log25 28 + log35 37 - log36 362
    = (8/5)log22 + (7/5)log33 - 2log3636
    = 8/5 + 7/5 - 2 = 1


  1. Find the value of log49 16807 - log9 27 ?









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    Exp. = log4916807 - log927
    = log72 75 - log32 33
    =(5/2)log77 - (3/2)log33

    Correct Option: B

    Exp. = log4916807 - log927
    = log72 75 - log32 33
    =(5/2)log77 - (3/2)log33
    =5/2 - 3/2
    = 1