I'm having the worst time coming up with the answer. Please help.
(sqrt (6.4 * 10^-n)^(-1/3)) = 5 When n=?
Thanks
negative fractional exponents
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First take the left partfastordie wrote:I'm having the worst time coming up with the answer. Please help.
(sqrt (6.4 * 10^-n)^(-1/3)) = 5 When n=?
Thanks
(sqrt (6.4 * 10^-n)^(-1/3))
(6.4 / 10^n)^ 1/2*-1/3=> (6.4 /10^n)^-1/6
=>64/(10^n+1))^-1/6 =>( (10^n+1) * 64)^1/6
=> ( (10^n+1) / 64)^1/6 =>( (10^n+1) ^1/6 ) / 64^1/6
=>( (10^n+1) ^1/6 ) /2 = 5 (As per the given)
(10^n+1) ^1/6 =10
(10^n+1 ) =10^6
=> n+1=6 => n=5
Hope it helps
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how did you go from ( (10^n+1) * 64)^1/6 to ( (10^n+1) / 64)^1/6 ???stubbornp wrote: First take the left part
(sqrt (6.4 * 10^-n)^(-1/3))
(6.4 / 10^n)^ 1/2*-1/3=> (6.4 /10^n)^-1/6
=>64/(10^n+1))^-1/6 =>( (10^n+1) * 64)^1/6
=> ( (10^n+1) / 64)^1/6 =>( (10^n+1) ^1/6 ) / 64^1/6
=>( (10^n+1) ^1/6 ) /2 = 5 (As per the given)
(10^n+1) ^1/6 =10
(10^n+1 ) =10^6
=> n+1=6 => n=5
Hope it helps
I think you may have left off a sign or something.
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