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Express in terms of powers of prime numbers Watch

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    Hi I'm a mech. eng undergraduate, and i have an exam next week so im powering through the past papers

    ive come across this question

    46 x 93 / 54 x 83 x 32

    it says express it in terms of powers of prime numbers

    now first of all can someone explain to me what that means? My lecturers are completely useless as frankly they do not give a f and ive been sitting here trying to figure this one out.

    i understand you have to make the bases the same in order to get anywhere, but HOW

    im completely stumped

    i would appreciate a prod in the right direction

    thank you in advance!
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    (Original post by n0cturnal)
    Hi I'm a mech. eng undergraduate, and i have an exam next week so im powering through the past papers

    ive come across this question

    46 x 93 / 54 x 83 x 32

    it says express it in terms of powers of prime numbers

    now first of all can someone explain to me what that means? My lecturers are completely useless as frankly they do not give a f and ive been sitting here trying to figure this one out.

    i understand you have to make the bases the same in order to get anywhere, but HOW

    im completely stumped

    i would appreciate a prod in the right direction

    thank you in advance!
    4^6 = (2^2)^6 = 2^12 where 2 is a prime

    9^3 = (3^2)^3 = 3^6 where 3 is prime

    Do this for all the numbers, cancel out common factors and you'll have a product of powers of primes.
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    cheers man! looks like i wasted a few hours over nothing!
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    (Original post by n0cturnal)
    cheers man! looks like i wasted a few hours over nothing!
    Ah, that's annoying! Glad it's sorted now.
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    i sent you a pm but im going to post this here again for anybody elses benefit who may be struggling

    ive got another question...

    64 x 55 / 65 x 63

    im trying to write out each individual number so

    64 would equal 22 x 32 am i correct?

    following that logic im getting 22 x 32 x 55 / 23 x 32 x 23 x 30

    but my final answer is still wrong

    the thing is i wouldnt know if my answer was wrong or right if i didnt have the answer sheet and im confused af right now
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    need to post this excellent reply here just in case somebody else may be struggling

    (Original post by Zacken)
    Remember, you can always check your logic with a calculator! 6 = 2 * 3So 6^4 = (2 * 3)^4 = 2^4 * 3^4This works if you enter 2^4 * 3^4 in your calculator, then clear. Then 6^4 and see if you get the same answer. Can you work out the rest of the question correctly now? Use the rule that (a \times b)^c = a^c \times b^c
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    (Original post by n0cturnal)
    i sent you a pm but im going to post this here again for anybody elses benefit who may be struggling

    ive got another question...

    64 x 55 / 65 x 63

    im trying to write out each individual number so

    64 would equal 22 x 32 am i correct?

    following that logic im getting 22 x 32 x 55 / 23 x 32 x 23 x 30

    but my final answer is still wrong

    the thing is i wouldnt know if my answer was wrong or right if i didnt have the answer sheet and im confused af right now
    Not really sorry. I will help you with one numbe
    64=32x2=2^6 try do this method for the other numbers.
    Then use indices rules and cancle.


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