Solving exponential equations with different bases

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  • čas přidán 19. 03. 2023
  • 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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Komentáře • 20

  • @skinnyladd
    @skinnyladd Před rokem +23

    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 Před rokem +8

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

  • @quantumnoctemus
    @quantumnoctemus Před 4 měsíci +3

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

  • @neilgerace355
    @neilgerace355 Před rokem +9

    "Surprising, right?"
    Hahahaha

  • @inmu5529
    @inmu5529 Před 8 dny

    2:00 his humor is crazy

  • @real_u23
    @real_u23 Před rokem +21

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

  • @thomassidoti5496
    @thomassidoti5496 Před 27 dny

    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

  • @balduran2003
    @balduran2003 Před 3 měsíci +1

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

  • @sanjaybhowmick4905
    @sanjaybhowmick4905 Před rokem +4

    I am highly impressed sir

  • @tutorchristabel
    @tutorchristabel Před rokem +1

    Well explained

  • @leonardobarrera2816
    @leonardobarrera2816 Před rokem +1

    That is a good one!!!

  • @sebastianjohansen2142
    @sebastianjohansen2142 Před 7 měsíci

    crazy guy

  • @ptrakoo5363
    @ptrakoo5363 Před 4 měsíci

    What is 2 log base2 of 3

  • @TheNerdess
    @TheNerdess Před 8 měsíci

    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 Před 6 měsíci

      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

  • @boredafmetoo7467
    @boredafmetoo7467 Před rokem

    Nice Shoes and nice video also

  • @mccauleybacalla2228
    @mccauleybacalla2228 Před rokem

    wow

  • @lookingforahookup
    @lookingforahookup Před 7 měsíci

    Isn’t (2^2)^x equal 4^x?

  • @graemehumfrey3955
    @graemehumfrey3955 Před 8 měsíci

    Beautiful