One more problem:

Find all $\displaystyle k \in R$ so that inequalities $\displaystyle log_{(x-1)^2}(x+5)^4\geq1$ and $\displaystyle log_{x+k}(x+3)\leq1$ have no mutual solutions.

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- Jan 29th 2013, 12:56 PMdarenceLogarithm
One more problem:

Find all $\displaystyle k \in R$ so that inequalities $\displaystyle log_{(x-1)^2}(x+5)^4\geq1$ and $\displaystyle log_{x+k}(x+3)\leq1$ have no mutual solutions. - Jan 29th 2013, 03:55 PMchiroRe: Logarithm
Hey darence.

Can you show us what you have tried (Hint: try expanding the definitions using log laws for change of base and powers and get an expression with k on one side of the inequality)? - Jan 30th 2013, 03:03 AMdarenceRe: Logarithm
That's my biggest problem. I don't know where to start from with this problem

- Jan 30th 2013, 01:38 PMchiroRe: Logarithm
Hint: log_a(x) = ln(x)/ln(a) [Change of Base Rule] and ln(a^x) = x*ln(a)