Solving exponential equations with different bases

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  • Опубликовано: 5 ноя 2024
  • How do we solve exponential equations with different bases? Oh well, make the bases the same first! Sometimes it's easy, sometimes we might have to use a log property that b^logb(x)=x
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Комментарии • 28

  • @skinnyladd
    @skinnyladd Год назад +30

    for the second equation I did,
    (2^4x) x 2 = 3^x
    (16^x) x 2 = 3^x
    (3^x)/(16^x) = 2
    (3/16)^x = 2
    Taking log base (3/16) on both sides
    x = log base 3/16 (2)
    x = -0.414 (which is the same as yours)
    great problems, looking forward to more!

  • @l.w.paradis2108
    @l.w.paradis2108 Год назад +10

    I like how this was explained so clearly and simply. Crisp, without needless complications.

  • @quantumnoctemus
    @quantumnoctemus 8 месяцев назад +6

    He teaches better in one second than many teachers in 1 hour.

  • @inmu5529
    @inmu5529 4 месяца назад +6

    2:00 his humor is crazy

  • @balduran2003
    @balduran2003 8 месяцев назад +1

    It's cool how the answer to the second one still has 1,2,3,4 in it.

  • @maroonjacketdkid08
    @maroonjacketdkid08 Год назад +29

    so that's when "log that's not base e" is important 😮

    • @charlescox290
      @charlescox290 Месяц назад

      I'm some of my computer science classes, lg was used as a convention for log base 2.

  • @sanjaybhowmick4905
    @sanjaybhowmick4905 Год назад +4

    I am highly impressed sir

  • @neilgerace355
    @neilgerace355 Год назад +9

    "Surprising, right?"
    Hahahaha

  • @weggquiz
    @weggquiz Год назад +1

    Well explained

  • @LythMusic
    @LythMusic 4 месяца назад

    (3x+1)log2 = xlog4
    3xlog2 + log2 = xlog4
    3xlog2 - xlog4 = -log2
    x(3log2-log4) = -log2
    x = -log2/3log2-log4

  • @thomassidoti5496
    @thomassidoti5496 5 месяцев назад

    I love this guy. It's just funny because if he would have just took the ln of 2 and 3 in the first place he wouldn't have to re-write the answer

  • @NapasimisOrdibarata
    @NapasimisOrdibarata 3 месяца назад

    It also the x is ²log (3/16)

  • @gruinfield1129
    @gruinfield1129 Месяц назад

    I did a more tedious method and got log2/log3-log2(4) which is still correct

  • @geopediashorts
    @geopediashorts 2 месяца назад

    i just used the property of logarithms, where you put the exponent in front of the logarithm

  • @leonardobarrera2816
    @leonardobarrera2816 Год назад +1

    That is a good one!!!

  • @zurinakasim2918
    @zurinakasim2918 2 месяца назад

    (4x+1)ln2=xln3
    4xln2+ln2=xln3
    xln16+ln2=xln3
    ln2=x(ln3-ln16)
    x=ln2/(ln3-ln16)

  • @TheNerdess
    @TheNerdess Год назад

    Im supposed to solve using only natural log. that has been my problem finding examples of people solving with that and not log! Stuff like 2^(5x+4)=3^(3x-2) can you just write ln instead of log?

    • @carultch
      @carultch 10 месяцев назад

      Since we have the change-of-base rule, it is arbitrary whether you write ln(8)/ln(2) or log(8)/log(2). Both produce the same result. You can solve any problem involving logs, using either natural log or log base ten. Or even some completely different base like log base 2.
      To do the problem you provided using natural log:
      Given: 2^(5*x+4) = 3^(3*x - 2)
      Take the natural log of both sides:
      ln(2^(5*x + 4)) = ln(3^(3*x - 2))
      Use the log property, ln(a^b) = b*ln(a) to pull the exponents out in front:
      (5*x + 4)*ln(2) = (3*x - 2)*ln(3)
      Expand, move constants to the right, and variables to the left:
      5*x*ln(2) + 4*ln(2) = 3*x*ln(3) - 2*ln(3)
      5*x*ln(2) - 3*x*ln(3) = -2*ln(3) - 4*ln(2)
      Factor the left:
      [5*ln(2) - 3*ln(3)]*x = -2*ln(3) - 4*ln(2)
      Isolate x:
      x=[-2*ln(3) - 4*ln(2)]/[5*ln(2) - 3*ln(3)]
      This can simplify to:
      x = -ln(144)/ln(32/27), which evaluates to about -29.25

  • @sebastianjohansen2142
    @sebastianjohansen2142 11 месяцев назад +1

    crazy guy

  • @ptrakoo5363
    @ptrakoo5363 8 месяцев назад

    What is 2 log base2 of 3

  • @neilkarlosnatividad4892
    @neilkarlosnatividad4892 4 дня назад

    I shouted NO ******* WAY for the second equation

  • @boredafmetoo7467
    @boredafmetoo7467 Год назад

    Nice Shoes and nice video also

  • @graemehumfrey3955
    @graemehumfrey3955 Год назад

    Beautiful

  • @DavidOlukoga
    @DavidOlukoga 3 месяца назад

    Those nikes bruh

  • @mccauleybacalla2228
    @mccauleybacalla2228 Год назад

    wow