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Math Help - SAT exponent problems

  1. #1
    Senior Member vaironxxrd's Avatar
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    SAT exponent problems

    I'm getting ready for my Sat and I believe I am going to fail on this math section .



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    Quote Originally Posted by vaironxxrd View Post
    I'm getting ready for my Sat and I believe I am going to fail on this math section .
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    4^b=(4)^b=(2^2)^b=2^{2b}
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    Senior Member vaironxxrd's Avatar
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    Quote Originally Posted by Plato View Post
    4^b=(4)^b=(2^2)^b=2^{2b}
    still cant get the hang of it
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    RULE: (x^a)^b = x^(ab)

    TRY it: let's use x = 2, a = 3, b = 4
    x^a = 2^3 = 8 ; 8^4 = 4096
    2^(3*4) = 2^12 = 4096
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  5. #5
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    Well, you are going to have to tell us exactly where you are having problems. Do you understand that 2^2= 4? Do you know that, for any numbers, a, m, and n, (a^m)^n= a^{mn}?
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    Senior Member vaironxxrd's Avatar
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    Quote Originally Posted by HallsofIvy View Post
    Well, you are going to have to tell us exactly where you are having problems. Do you understand that 2^2= 4? Do you know that, for any numbers, a, m, and n, (a^m)^n= a^{mn}?
    I like always am just confusing myself.

    Seeing what the question is asking me makes me think that 2^4=4^2 but since they are variables I don't know what to do with them
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    The first thing to do is to get them to the same base. Since you are told these two things are equal, if the bases are equal, so must be the exponents.
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    Senior Member vaironxxrd's Avatar
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    Quote Originally Posted by Prove It View Post
    The first thing to do is to get them to the same base. Since you are told these two things are equal, if the bases are equal, so must be the exponents.
    2^2=4^2?
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    Hi vaironxxrd,
    2 squared is not equal to 4squared


    if a >0 and not = to 1 then if a^m = a^n m=n
    example 8^x = 2^9 find x
    (2^3)^x = 2^3x = 2^9
    3x=9
    x=3



    bjh
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    Quote Originally Posted by bjhopper View Post
    Hi vaironxxrd,
    2 squared is not equal to 4squared
    if a >0 and not = to 1 then if a^m = a^n m=n
    example 8^x = 2^9 find x
    (2^3)^x = 2^3x = 2^9
    3x=9
    x=3bjh
    I would hate to see vaironxxrd's score on even the PSAT!
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    Senior Member vaironxxrd's Avatar
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    Quote Originally Posted by Plato View Post
    I would hate to see vaironxxrd's score on even the PSAT!
    Probably Ill get 1 question right. Thanks for the motivation there
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    Quote Originally Posted by vaironxxrd View Post
    Probably Ill get 1 question right. Thanks for the motivation there
    Well, you have to agree that it's difficult to know HOW to help you:

    in one post, you ask if 2^2 = 4^2;
    it's evident that's not an equality, since 2^2 = 4 and 4^2 = 16;
    so what are we to think...

    then you state:
    "Seeing what the question is asking me makes me think that 2^4=4^2
    but since they are variables I don't know what to do with them " :
    that's correct: so the variables a = 4 and b = 2;
    but you seem unaware that a is twice b (4 is twice 2, right?), so a = 2b.
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    Senior Member vaironxxrd's Avatar
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    Quote Originally Posted by Wilmer View Post
    Well, you have to agree that it's difficult to know HOW to help you:

    in one post, you ask if 2^2 = 4^2;
    it's evident that's not an equality, since 2^2 = 4 and 4^2 = 16;
    so what are we to think...

    then you state:
    "Seeing what the question is asking me makes me think that 2^4=4^2
    but since they are variables I don't know what to do with them " :
    that's correct: so the variables a = 4 and b = 2;
    but you seem unaware that a is twice b (4 is twice 2, right?), so a = 2b.
    I do have to accept my lack of understanding things .
    Thanks now I do understand it, but I just could not figure out what the question was asking me.

    By the way like I stated earlier I confused myself.
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    Quote Originally Posted by vaironxxrd View Post
    I do have to accept my lack of understanding things .
    Thanks now I do understand it, but I just could not figure out what the question was asking me.
    By the way like I stated earlier I confused myself.
    Don't give up...with practice (as is the case with anything else), you'll become an expert !
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    Senior Member vaironxxrd's Avatar
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    Quote Originally Posted by Wilmer View Post
    Don't give up...with practice (as is the case with anything else), you'll become an expert !
    I could agree with that statement since last year I was horrible in school and had F in Geometry. Now I pushed myself to be dedicated to my homework found this forum, etc.. and Now I'm a honor roll student ,but the SAT just drains my motivation out.
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