log4 x - log4 (x-3) = 5
The Attempt at a Solution
log4 x/x-3 = 5
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x = 1024 - 3072I think you're missing something very simple. You've got an equation in which you must what numerical value hides under 'x'.
So [itex] x= 1024\cdot (x-3) = 1024\cdot x - 1024\cdot 3 = 1024\cdot x - 3072 [/itex]
Now subtract x from both terms of [itex] x= 1024\cdot x - 3072 [/itex].
What do you get ?
Well then you need to go back and cover basic algebra again. You can't afford to lose that many marks on logarithms just because you don't know your algebra.as u can see i am not good at this, ok here goes
Yes and now? If I asked you to solve for x why haven't you given us x=... ?1024x-x=3072
1023x = 3072
i dont understand how to do thatYes, now just go back and check to see if your solutions are valid in the original question. That is, everything that you take the logarithm of needs to be greater than zero, so x>0 and x-3>0, therefore x>3. Since both of these need to be satisfied, we just consider x>3. Is your solution valid?