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= (3^x-1)^3elimenda wrote:if 3^6x= 8100, what is the value of (3^x-1)^3?
jnellaz wrote:Thanks Logitech. I hate to be a stickler for detail but I am really trying hard to understand and implement each of the rules for exponents correctly. (Unfortunately, I don't have 4 years of engineering!) You posted
= (3^x-1)^3
= 3^3x-3
Isn't (3^x-1)^3 equal to (3^3x-1^3 )
= (3^3x-1)
Please let me know where I went wrong. As always, thanks!
logitech wrote:= (3^x-1)^3elimenda wrote:if 3^6x= 8100, what is the value of (3^x-1)^3?
= 3^3x-3
= 3^3X / 3^3 (i)
3^6x= 8100
3^3x = 90 (ii)
If we combine (i) + (ii)
= 3^3X / 3^3
= 90/27
= 10/3
cartera wrote:Hi Logitech
In the point II, how did you get 3^3x=90?
logitech wrote:= (3^x-1)^3elimenda wrote:if 3^6x= 8100, what is the value of (3^x-1)^3?
= 3^3x-3
= 3^3X / 3^3 (i)
3^6x= 8100
3^3x = 90 (ii)
3^6x= 8100 (TAKE SQUARE ROOT OF BOTH SIDES)
and you will get:
3^3x = 90 (ii)
If we combine (i) + (ii)
= 3^3X / 3^3
= 90/27
= 10/3
