Question

3^(x+1) X 2^(x-2) =21

Answer 1

have you attempted this?

Answer 2

I can't yet see through to the solution.

Answer 3

i have an answer x = log28/log6

Answer 4

anyone else?

Answer 5

How do you do this?

Answer 6

is that the answer you have?

Answer 7

i'll have to go soon

Answer 8

Nope,it's 1.86

Answer 9

1.86 happens to be log28/log6 on my calculator!!

Answer 10

Alright,then how to do you do this question?

Answer 11

Its not easy but here it goes......

1st step is to take the logs of both sides

log[3^(x+1).2^(x-2)] = log21

then we get

log[3^(x+1)] + log[2^(x-2)] = log21

follow so far?

Answer 12

So we use product aw here?

Answer 13

*law

Answer 14

yes that's right


next step

(x+1)log3 + (x-2)log2 = log21

Answer 15

now we expand and separate into like terms

x(log3 + log2) = log21 + log4 - log3

happy with that?

Answer 16

Yes,very much

Answer 17

ok now we get to the final result

xlog6 = log(21x4/3)

x = log28/log6 = 1.86 (2 sig figs)

Answer 18

there you go!

Answer 19

Thanks a lot :D

Answer 20

no problem. you're welcome.

i hope you really understand the steps

Answer 21

I'll just take some time to let it all get in,I'll manage.