Results 1 to 9 of 9

Math Help - calculator help

  1. #1
    Member
    Joined
    Jul 2008
    Posts
    128
    Awards
    1

    calculator help

    i need to know how to get this on a calculator

    81 = 3 power of 4

    25 = 5 power of 2

    if anyone knows how to do it with there calc i can prolly apply it to mine thanks
    Follow Math Help Forum on Facebook and Google+

  2. #2
    No one in Particular VonNemo19's Avatar
    Joined
    Apr 2009
    From
    Detroit, MI
    Posts
    1,823
    Quote Originally Posted by realistic View Post
    i need to know how to get this on a calculator

    81 = 3 power of 4

    25 = 5 power of 2

    if anyone knows how to do it with there calc i can prolly apply it to mine thanks
    The ^ button means "raised to the" .
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Member
    Joined
    Jul 2008
    Posts
    128
    Awards
    1
    Quote Originally Posted by VonNemo19 View Post
    The ^ button means "raised to the" .
    hi i can get 3 ^ 4 = 81

    however i need the reverse how to get 3 ^4
    Follow Math Help Forum on Facebook and Google+

  4. #4
    No one in Particular VonNemo19's Avatar
    Joined
    Apr 2009
    From
    Detroit, MI
    Posts
    1,823
    Quote Originally Posted by realistic View Post
    hi i can get 3 ^ 4 = 81

    however i need the reverse how to get 3 ^4
    AAAAAAAAAAhhhh. I see. Well, I'm with you, then. I'd like to know if a calculator could do that, too. However, I must say that factoring is probably quiker than picking up the calculator...
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Member
    Joined
    Jul 2008
    Posts
    128
    Awards
    1
    Quote Originally Posted by VonNemo19 View Post
    AAAAAAAAAAhhhh. I see. Well, I'm with you, then. I'd like to know if a calculator could do that, too. However, I must say that factoring is probably quiker than picking up the calculator...
    for example if i have 625 is there a fast way to find out its 5^4

    just takes me too long sometimes to do it
    Follow Math Help Forum on Facebook and Google+

  6. #6
    No one in Particular VonNemo19's Avatar
    Joined
    Apr 2009
    From
    Detroit, MI
    Posts
    1,823
    Quote Originally Posted by realistic View Post
    for example if i have 625 is there a fast way to find out its 5^4

    just takes me too long sometimes to do it
    Numbers are great! When I see the number 625, I automatically say to myself that this is divisible by 25. Then I have 625=25\cdot25

    And the rest is history...
    Follow Math Help Forum on Facebook and Google+

  7. #7
    MHF Contributor
    Joined
    Dec 2007
    From
    Ottawa, Canada
    Posts
    3,161
    Thanks
    70
    Quote Originally Posted by realistic View Post
    for example if i have 625 is there a fast way to find out its 5^4
    If you're not given the 5 or the 4, then there's no "fast way".
    Follow Math Help Forum on Facebook and Google+

  8. #8
    Member
    Joined
    Jul 2008
    Posts
    128
    Awards
    1
    Quote Originally Posted by Wilmer View Post
    If you're not given the 5 or the 4, then there's no "fast way".
    ok, say you are given the 5 how do you enter it in the calculator to get the ^ 4
    Follow Math Help Forum on Facebook and Google+

  9. #9
    MHF Contributor
    Joined
    Dec 2007
    From
    Ottawa, Canada
    Posts
    3,161
    Thanks
    70
    You then need 5^x = 625.
    So x = log(625) / log(5) ; got an "ln" key on your calculator?

    If 4 is the given, then x^4 = 625.
    So x = 625^(1/4).

    Tattoo this on your wrist (under your watch!):
    If a^b = c, then a = c^(1/b)
    If a^b = c, then b = log(c) / log(a)
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 2
    Last Post: May 6th 2012, 03:16 PM
  2. help with my calculator
    Posted in the Calculators Forum
    Replies: 2
    Last Post: December 6th 2011, 05:50 AM
  3. Without the use of a calculator
    Posted in the Algebra Forum
    Replies: 2
    Last Post: November 14th 2009, 12:28 PM
  4. calculator
    Posted in the Algebra Forum
    Replies: 7
    Last Post: June 1st 2008, 10:30 PM
  5. calculator help
    Posted in the Algebra Forum
    Replies: 1
    Last Post: May 22nd 2008, 07:24 PM

Search Tags


/mathhelpforum @mathhelpforum