Mathematics
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OpenStudy (anonymous):
1) log x^2 with base 6 = 4 help me please
2) log x^1/2 with base 2 = 1/2
3) 8^(x^2-x) = 32 ^(1-x)
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hartnn (hartnn):
so you know
\(\Large \log_ab=c \implies b=a^c \)
?
OpenStudy (anonymous):
Hey, you again :)
hartnn (hartnn):
hi, yes :)
OpenStudy (anonymous):
yes. you're amazing the way you teach, youll let the viewer understand
hartnn (hartnn):
thank you for the compliment!
i feel happy when i make someone understand something :)
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hartnn (hartnn):
so ,what about log x^2 with base 6 = 4
?
OpenStudy (anonymous):
6^4 = x^2?
hartnn (hartnn):
and you were typing something ? feel free to interact :)
hartnn (hartnn):
absolutely correct!
just take square root on both sides to get 'x'
hartnn (hartnn):
so which 2 values of x did u get ?
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OpenStudy (anonymous):
soo its 36! ^_^
OpenStudy (anonymous):
am i right?
hartnn (hartnn):
yes! and other value ?
hartnn (hartnn):
oh, wait!
OpenStudy (anonymous):
is there any other value?
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hartnn (hartnn):
yes,
x^2 = 36^2
----> x^2-36^2 = 0
(x+36)(x-36) =0
x = -36, x=36
got this ?
hartnn (hartnn):
while taking square root we consider both \(\pm\) values
hartnn (hartnn):
make sense ?
OpenStudy (anonymous):
anyway why is it that 36 was raised by 2?
hartnn (hartnn):
6^4 = (6^2)^2 = (36)^2
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OpenStudy (anonymous):
number 2 pleasee
myininaya (myininaya):
\[\log_2(x^2)=\frac{1}{2}\]
Try write in exponential form.
\[\log_a(y)=x \text{ equivalent to } a^x=y \]
OpenStudy (anonymous):
2^1/2 = x ^ 1/2
OpenStudy (anonymous):
2^1/2 = x ^ 1/2
myininaya (myininaya):
the inside of the log is x^2, correct?
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myininaya (myininaya):
well for my problem it is
myininaya (myininaya):
for your problem above inside is x^1/2
myininaya (myininaya):
Ok what does that imply x is?
myininaya (myininaya):
\[x^\frac{1}{2}=2^\frac{1}{2} \]
just look by inspect...
what would x have to be in order for both sides to be the same.
OpenStudy (anonymous):
so x would be 2/? thanlks
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myininaya (myininaya):
yes x would be 2 since 2^1/2=2^1/2
OpenStudy (anonymous):
how about my problem number 3
myininaya (myininaya):
Write 8 as 2^something
Write 32 as 2^something
myininaya (myininaya):
Goal get the same base on both sides.
myininaya (myininaya):
2^1=2
2^2=2*2=4
2^3=2*2*2=4(2)=8
2^4=2*2*2*2=8(2)=16
....
What is 2^5?
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OpenStudy (anonymous):
8 as 2^3 and 32 = 2 ^ 5
myininaya (myininaya):
yes
myininaya (myininaya):
\[2^{3(x^2-x)}=2^{5(1-x)}\]
myininaya (myininaya):
if a^x=a^y then a=y.
myininaya (myininaya):
So set your exponents equal and solve for x.
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OpenStudy (anonymous):
so 3 (x^2 - 3x) = 5(1-x) shall i distribute it?
myininaya (myininaya):
yes
OpenStudy (anonymous):
3x^2 - 3x = 5 = 5x what would be next?
myininaya (myininaya):
3(x^2-x)=5(1-x)
3x^2-3x=5-5x
Put everything on one side.
OpenStudy (anonymous):
3x^2 + 2x = 5?
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myininaya (myininaya):
Ok then subtract 5 on both sides.
You can then use the quadratic formula.
OpenStudy (anonymous):
you mean 3x^2 + 2x - 5 = 0 than factor it out?
myininaya (myininaya):
You can use quadratic formula or factoring.
OpenStudy (anonymous):
how is it done please
OpenStudy (anonymous):
i find it hard on factoring
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myininaya (myininaya):
What two factors of a*c have product ac and sum b?
What two factors of -15 have product -15 and sum 2?
OpenStudy (anonymous):
gonna finish it tomorrow, i'll study this buy tomorrow for it's time for me to sleep. it\s already 1 am here. how about there?
OpenStudy (anonymous):
thankyou so much for helping me. see ya
myininaya (myininaya):
noon time
OpenStudy (anonymous):
aw, yeah, so goodbye for bow. I'll be right back. thankyou so much! its time for me to sleep
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OpenStudy (anonymous):
*now
hartnn (hartnn):
have sweet dreams! :)