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A2 ln sum

lny=3ln(x^2+4)+ln32-3ln4

the answer is y= 0.5(x^2+4)

No matter how I do it,I end up with a cube over x^2+4.please help...
Original post by economist2
lny=3ln(x^2+4)+ln32-3ln4

the answer is y= 0.5(x^2+4)

No matter how I do it,I end up with a cube over x^2+4.please help...


Get it all in terms of one big log.

Use n log(a) = log(a^n)
log(a) + log(b) = log(ab)
and log(a)-log(b) = log(a/b)

Just checked and their answer doesn't look right to me.

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(edited 9 years ago)
Reply 2
Original post by economist2
lny=3ln(x^2+4)+ln32-3ln4

the answer is y= 0.5(x^2+4)

No matter how I do it,I end up with a cube over x^2+4.please help...


The answer that you have been given is wrong.
Reply 3
thanks.I should be more confident.

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