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November 6th, 2009, 11:02 PM
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| |  Basic Logirithms & Basic expanding the brackets
Hello everyone,
I need help with logarithms that are in fraction form.
such as
evaluate the following for x:
log ^ 2 x = 1/7
log ^ 2 x = 1/5
log ^ 2 x = 2/7
I also need to be sure if expanding this equation for e.g is correct?
expand the following:
(a + b) (a + b + c)
a^2 + ab + ac + ba + b^2 + bc
& do I plus the powers or times them in the brackets?
expand the following:
(a^2 + b^2) (a^3 + b^3 + c^2)
a^5 + a^2b^5 + a^2c^2 + b^2a^3 + b ^ 5 + b ^2c^ 2 |
November 6th, 2009, 11:19 PM
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November 6th, 2009, 11:19 PM
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Quote:
Originally Posted by student0451  Hello everyone,
I need help with logarithms that are in fraction form.
such as
evaluate the following for x:
log ^ 2 x = 1/7
log ^ 2 x = 1/5
log ^ 2 x = 2/7
I also need to be sure if expanding this equation for e.g is correct?
expand the following:
(a + b) (a + b + c)
a^2 + ab + ac + ba + b^2 + bc
& do I plus the powers or times them in the brackets?
expand the following:
(a^2 + b^2) (a^3 + b^3 + c^2)
a^5 + a^2b^5 + a^2c^2 + b^2a^3 + b ^ 5 + b ^2c^ 2 | 1. Do you mean  or  ?
2. Collect your like terms
__________________ "Then thou carriedst thine ashes into the mountains: wilt thou now carry thy fire into the valleys?" Thus Spake Zarathustra Friedrich Nietzsche If you would like to know how the quadratic formula was derived, visit my post entitled: Deriving the Quadratic Formula. |
November 6th, 2009, 11:21 PM
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i am so sorry about my typing, http://www.mathhelpforum.com/math-he...6f55baf4-1.gif
it is the base of 2
log 2 x = 1/7
so 2 is the base of the log
and thank you for helping me. |
November 6th, 2009, 11:24 PM
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Then it becomes (I think) :  
When writing indicators, use the underscore char, it is much more appropriate : log_2(x). |
November 6th, 2009, 11:24 PM
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Quote:
Originally Posted by student0451 | ![\log_2x=\frac{1}{7}\Rightarrow{x}=2^{1/7}=\sqrt[7]{2}](http://www.mathhelpforum.com/math-help/latex2/img/05b6dc24f167b82a2b5f7126b224aa15-1.gif "\log_2x=\frac{1}{7}\Rightarrow{x}=2^{1/7}=\sqrt[7]{2}")
__________________ "Then thou carriedst thine ashes into the mountains: wilt thou now carry thy fire into the valleys?" Thus Spake Zarathustra Friedrich Nietzsche If you would like to know how the quadratic formula was derived, visit my post entitled: Deriving the Quadratic Formula. |
November 6th, 2009, 11:28 PM
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yep
and thank you, vondera19 & Bacterius.
I knew there was something wrong between the way I expanded brackets. | | Thread Tools | | | | Display Modes |  Linear Mode | 
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